add component-based hybrid system test

[baggepinnen]

This PR adds a test for a hybrid system constructed from components. It exposes a few problems:

• There is a delay of exactly 1 sample interval in the output. I have not yet located the source of the delay. I think the problem is that d2c_view needs to be initialized correctly, it currently starts out as 0. Missing initialization of discrete-to-continuous communication parameter #2356
• All variables associated with the discrete partition are zero in the solution, including observed variables
• The fact that Hold is an operator precludes its use as a component with the same name. We could consider renaming the operator hold to avoid the conflict. The same goes for the operator Sample, but in this case I find the component name Sampler okay (whereas Holder isn't great 😅 )

I added some tests that are marked as broken are fixed, tracked by

• Missing initialization of discrete-to-continuous communication parameter #2356

Additionally, issue

• Failure to normalize negative shifts #2358
  was discovered

[YingboMa]

Tests passed locally for me.