Remove CVC4-only verification
The CVC4-only verification tests almost always fail in our CI for no apparent reason. Neither an error message nor a log of the failing step is provided. We should disable those tests until we found a solution for this issue.
Alternative CI offerings:
Is there a way to comment it out and add a comment pointing to a Workaround so we don't forget to re-enable it in the future?
Maybe. I would just keep this issue open until we find a solution. I think that is sufficient in this case.
Then let's leave it open until the issue is fixed.
Decision: Remove prove_tests_cvc4 make target in Makefile and prove_cvc4 in tests/spark/Makefile. This does not make sense right now as we don't have two provers which are able to reliably prove our code alone.