Drop support for python 3.7

[jvesely]

Bump minimum rich requirement.
Restrict 32-bit job to last available wheels.
Drop Python3.7 CI jobs.
Bump minimum Python requirement to 3.8

[davidt0x]

LGTM

[github-actions]

This PR causes the following changes to the html docs (ubuntu-latest-3.11):

diff -r docs-base/TransferFunctions.html docs-head/TransferFunctions.html
2361c2361
< <p><a class="reference internal" href="#psyneulink.core.components.functions.transferfunctions.Exponential.bounds" title="psyneulink.core.components.functions.transferfunctions.Exponential.bounds"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">bounds</span></code></a> – specifies the lower and upper limits of the result;  if there are none, the attribute is set to
---
> <p><a class="reference internal" href="OptimizationFunctions.html#psyneulink.core.components.functions.optimizationfunctions.GradientOptimization.bounds" title="psyneulink.core.components.functions.optimizationfunctions.GradientOptimization.bounds"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">bounds</span></code></a> – specifies the lower and upper limits of the result;  if there are none, the attribute is set to

...

See CI logs for the full diff.

[jvesely]

I planned to delay this change until #3071 is submitted to have one last release with 3.7 support.
Let me know if it'd be better to have this before the release.

[kmantel]

I agree one last release seems good. I was delaying #3071 hoping to get something like #3078 in. That copies the 3.7 jobs from other ci currently.

In this case I also think it would be nice to include something for the Condition IDE tooltips (condition-names), but that's not fully finalized yet. If 3.7 is blocking something, then I don't think it's important.

[github-actions]

This PR causes the following changes to the html docs (ubuntu-latest-3.11):

diff -r docs-base/TransferFunctions.html docs-head/TransferFunctions.html
2199c2199
< <p><a class="reference internal" href="#psyneulink.core.components.functions.transferfunctions.Exponential.bounds" title="psyneulink.core.components.functions.transferfunctions.Exponential.bounds"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">bounds</span></code></a> – specifies the lower and upper limits of the result;  if there are none, the attribute is set to
---
> <p><a class="reference internal" href="OptimizationFunctions.html#psyneulink.core.components.functions.optimizationfunctions.GradientOptimization.bounds" title="psyneulink.core.components.functions.optimizationfunctions.GradientOptimization.bounds"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">bounds</span></code></a> – specifies the lower and upper limits of the result;  if there are none, the attribute is set to

...

See CI logs for the full diff.

[kmantel]

I left in the 3.7 job in test-release.yml; that could also be taken out here, unless it makes sense to continue to test the installation on 3.7 there

[github-actions]

This PR causes the following changes to the html docs (ubuntu-latest-3.11):

diff -r docs-base/LearningFunctions.html docs-head/LearningFunctions.html
1549c1549
< error_matrix passed in the <a class="reference internal" href="AutodiffComposition.html#psyneulink.library.compositions.autodiffcomposition.AutodiffComposition.PytorchCompositionWrapper.params" title="psyneulink.library.compositions.autodiffcomposition.AutodiffComposition.PytorchCompositionWrapper.params"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">params</span></code></a> argument.</p>
---
> error_matrix passed in the <a class="reference internal" href="DistributionFunctions.html#psyneulink.core.components.functions.distributionfunctions.ExponentialDist.params" title="psyneulink.core.components.functions.distributionfunctions.ExponentialDist.params"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">params</span></code></a> argument.</p>
diff -r docs-base/RefactoredLearningGuide.html docs-head/RefactoredLearningGuide.html
282c282
< <p>Notice that we no longer have to extract the target node from the <code class="xref any docutils literal notranslate"><span class="pre">add_backpropagation_learning_pathway</span> <span class="pre">method</span></code>, and can instead pass the targets as output nodes mapped to values, in a new parameter called <code class="xref any docutils literal notranslate"><span class="pre">targets</span></code> in the <a class="reference internal" href="AutodiffComposition.html#psyneulink.library.compositions.autodiffcomposition.AutodiffComposition.learn" title="psyneulink.library.compositions.autodiffcomposition.AutodiffComposition.learn"><code class="xref any py py-meth docutils literal notranslate"><span class="pre">learn</span></code></a> method.</p>
---
> <p>Notice that we no longer have to extract the target node from the <code class="xref any docutils literal notranslate"><span class="pre">add_backpropagation_learning_pathway</span> <span class="pre">method</span></code>, and can instead pass the targets as output nodes mapped to values, in a new parameter called <code class="xref any docutils literal notranslate"><span class="pre">targets</span></code> in the <a class="reference internal" href="EMComposition.html#psyneulink.library.compositions.emcomposition.EMComposition.learn" title="psyneulink.library.compositions.emcomposition.EMComposition.learn"><code class="xref any py py-meth docutils literal notranslate"><span class="pre">learn</span></code></a> method.</p>
287c287
< its constructor to be runtime parameters of its <a class="reference internal" href="AutodiffComposition.html#psyneulink.library.compositions.autodiffcomposition.AutodiffComposition.learn" title="psyneulink.library.compositions.autodiffcomposition.AutodiffComposition.learn"><code class="xref any py py-meth docutils literal notranslate"><span class="pre">learn</span></code></a> method.</p>
---
> its constructor to be runtime parameters of its <a class="reference internal" href="EMComposition.html#psyneulink.library.compositions.emcomposition.EMComposition.learn" title="psyneulink.library.compositions.emcomposition.EMComposition.learn"><code class="xref any py py-meth docutils literal notranslate"><span class="pre">learn</span></code></a> method.</p>
diff -r docs-base/TransferFunctions.html docs-head/TransferFunctions.html
2199c2199
< <p><a class="reference internal" href="OptimizationFunctions.html#psyneulink.core.components.functions.optimizationfunctions.GradientOptimization.bounds" title="psyneulink.core.components.functions.optimizationfunctions.GradientOptimization.bounds"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">bounds</span></code></a> – specifies the lower and upper limits of the result;  if there are none, the attribute is set to
---
> <p><a class="reference internal" href="#psyneulink.core.components.functions.transferfunctions.Exponential.bounds" title="psyneulink.core.components.functions.transferfunctions.Exponential.bounds"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">bounds</span></code></a> – specifies the lower and upper limits of the result;  if there are none, the attribute is set to

...

See CI logs for the full diff.

[github-actions]

This PR causes the following changes to the html docs (ubuntu-latest-3.11):

diff -r docs-base/ModulatoryProjection.html docs-head/ModulatoryProjection.html
272c272
< <a class="reference internal" href="Port.html"><span class="doc">Port</span></a> are listed in the Port’s <a class="reference internal" href="Mechanism.html#id7" title="psyneulink.core.components.mechanisms.mechanism.Mechanism_Base.mod_afferents"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">mod_afferents</span></code></a> attribute.</p>
---
> <a class="reference internal" href="Port.html"><span class="doc">Port</span></a> are listed in the Port’s <a class="reference internal" href="ParameterPort.html#psyneulink.core.components.ports.parameterport.ParameterPort.mod_afferents" title="psyneulink.core.components.ports.parameterport.ParameterPort.mod_afferents"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">mod_afferents</span></code></a> attribute.</p>
diff -r docs-base/Port.html docs-head/Port.html
616c616
< <code class="xref any docutils literal notranslate"><span class="pre">PathWayProjections</span></code> (listed in its <a class="reference internal" href="Mechanism.html#id6" title="psyneulink.core.components.mechanisms.mechanism.Mechanism_Base.path_afferents"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">path_afferents</span></code></a> attribute) as the variable for its
---
> <code class="xref any docutils literal notranslate"><span class="pre">PathWayProjections</span></code> (listed in its <a class="reference internal" href="#psyneulink.core.components.ports.port.Port_Base.path_afferents" title="psyneulink.core.components.ports.port.Port_Base.path_afferents"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">path_afferents</span></code></a> attribute) as the variable for its
diff -r docs-base/TransferFunctions.html docs-head/TransferFunctions.html
2199c2199
< <p><a class="reference internal" href="#psyneulink.core.components.functions.transferfunctions.Exponential.bounds" title="psyneulink.core.components.functions.transferfunctions.Exponential.bounds"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">bounds</span></code></a> – specifies the lower and upper limits of the result;  if there are none, the attribute is set to
---
> <p><a class="reference internal" href="OptimizationFunctions.html#psyneulink.core.components.functions.optimizationfunctions.GradientOptimization.bounds" title="psyneulink.core.components.functions.optimizationfunctions.GradientOptimization.bounds"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">bounds</span></code></a> – specifies the lower and upper limits of the result;  if there are none, the attribute is set to

...

See CI logs for the full diff.

[github-actions]

This PR causes the following changes to the html docs (ubuntu-latest-3.11):

diff -r docs-base/ModulatoryProjection.html docs-head/ModulatoryProjection.html
272c272
< <a class="reference internal" href="Port.html"><span class="doc">Port</span></a> are listed in the Port’s <a class="reference internal" href="ParameterPort.html#psyneulink.core.components.ports.parameterport.ParameterPort.mod_afferents" title="psyneulink.core.components.ports.parameterport.ParameterPort.mod_afferents"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">mod_afferents</span></code></a> attribute.</p>
---
> <a class="reference internal" href="Port.html"><span class="doc">Port</span></a> are listed in the Port’s <a class="reference internal" href="Mechanism.html#id7" title="psyneulink.core.components.mechanisms.mechanism.Mechanism_Base.mod_afferents"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">mod_afferents</span></code></a> attribute.</p>
diff -r docs-base/Port.html docs-head/Port.html
616c616
< <code class="xref any docutils literal notranslate"><span class="pre">PathWayProjections</span></code> (listed in its <a class="reference internal" href="#psyneulink.core.components.ports.port.Port_Base.path_afferents" title="psyneulink.core.components.ports.port.Port_Base.path_afferents"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">path_afferents</span></code></a> attribute) as the variable for its
---
> <code class="xref any docutils literal notranslate"><span class="pre">PathWayProjections</span></code> (listed in its <a class="reference internal" href="Mechanism.html#id6" title="psyneulink.core.components.mechanisms.mechanism.Mechanism_Base.path_afferents"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">path_afferents</span></code></a> attribute) as the variable for its
diff -r docs-base/TransferFunctions.html docs-head/TransferFunctions.html
2199c2199
< <p><a class="reference internal" href="OptimizationFunctions.html#psyneulink.core.components.functions.optimizationfunctions.GradientOptimization.bounds" title="psyneulink.core.components.functions.optimizationfunctions.GradientOptimization.bounds"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">bounds</span></code></a> – specifies the lower and upper limits of the result;  if there are none, the attribute is set to
---
> <p><a class="reference internal" href="#psyneulink.core.components.functions.transferfunctions.Exponential.bounds" title="psyneulink.core.components.functions.transferfunctions.Exponential.bounds"><code class="xref any py py-attr docutils literal notranslate"><span class="pre">bounds</span></code></a> – specifies the lower and upper limits of the result;  if there are none, the attribute is set to

...

See CI logs for the full diff.