Gearpump test configuration should exclude merging window tests

Looking at this Jenkins log we can see various messages about unsupported features. We should exclude these tests so that the Jenkins results are more helpful.

java.lang.UnsupportedOperationException: merging window is not supported in Gearpump pipeline

and

java.lang.IllegalStateException: no translator registered for View.CreatePCollectionView

These are clearly "side inputs" and "merging windows". And I think that would cover all the failures.