Minor fix for EnsemblePosterior weights.setter

[CompiledAtBirth]

What does this implement/fix? Explain your changes

In sbi.inference.posteriors, the EnsemblePosterior instantiation would return a TypeError when passing weights (torch.Tensor or List[float]). The condition elif weights is Tensor or weights is List would always return False, I changed the condition to elif isinstance(weights, Tensor) or isinstance(weights, List), where Tensor is the torch class of the same name.

Does this close any currently open issues?

No, to the best of my knowledge.

Any relevant code examples, logs, error output, etc?

The only "fix" is intended to properly test the type of the weights attribute of EnsemblePosterior in case it is not None.

Any other comments?

I do not know whether I should have opened an new issue instead of doing a minor one-line PR. I will leave empty most of the Checklist items below.
...

Checklist

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 78.43%. Comparing base (3d5cb24) to head (e535aca).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
sbi/inference/posteriors/ensemble_posterior.py	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #1299       +/-   ##
===========================================
- Coverage   89.30%   78.43%   -10.87%     
===========================================
  Files         119      119               
  Lines        8721     8732       +11     
===========================================
- Hits         7788     6849      -939     
- Misses        933     1883      +950     

Flag	Coverage Δ
unittests	78.43% <0.00%> (-10.87%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
sbi/inference/posteriors/ensemble_posterior.py	50.00% <0.00%> (-37.97%)	⬇️

... and 31 files with indirect coverage changes

[janfb]

this looks good. thanks for fixing this!

The linter action is failing because your proposed change can be simplified. I made a suggestion.

To proceed, please accept it to make sure the linter and the tests actions run through. Thanks

[janfb]

Looks good, thanks for fixing this! :problem