Add tests for JavaSMT delegates

[daniel-raffler]

We should add additional tests to verify that all delegates included with JavaSMT are working as expected. For now it should be enough to add some CPAchecker runs with different analyses to see if there are any issues

[PhilippWendler]

com.google.common.testing.ForwardingWrapperTester might be useful.

[baierd]

com.google.common.testing.ForwardingWrapperTester might be useful.

This looks actually SUPER helpful and exactly what we need!
@daniel-raffler ForwardingWrapperTester checks whether wrappers forward arguments and returns the returned values back. The link has examples for this. We should actually add tests for our wrappers using this! (But in a new PR)

[baierd]

Also, you could add a test-set to CPAcheckers solver test-sets with pre-configured delegates active. So that we have a consistent integration test.