Exclude Modelica.Clocked from the testing

[casella]

The status of clocked variables in BaseModelica is still debated. I would skip Modelica.Clocked models from https://openmodelica.github.io/BaseModelicaLibraryTesting.jl/results/main/Modelica/4.1.0/index.html, because even if they are now parsed successfully, chances are, they're not going to be correct.

[AnHeuermann]

We could exclude them, but it doesn't cost too much time to run them (37 sec on my machine, maybe 1-2 minutes on the GitHub servers). But the filter would be filter = "^(?!Modelica\\.Clocked)".
In my opinion we have a more complete picture of what is currently missing if we keep them enabled.

[casella]

It's not about the cost of testing. My point is that we have 17 models reported as running successfully, even though:

• we are not exporting Base Modelica code as mandated by the draft specification for clocked variables
• I have no idea how BaseModelica.jl is interpreting that code
• verification fails because of signals not found in the simulation result, despite it being reported as successful

This seems a bit messy to me.