CdmPermissionVoter handles merged and separate CdmAuthorities the same
The CdmPermissionVoter must take all CdmAuthorities into account which only differ by the property if any is defined at all.
TAXONBASE.[CREATE] TAXONBASE.[READ] TAXONBASE.[UPDATE] TAXONBASE.[DELETE]
should be handled exactly the same like.
see related cdmlib|5cb08c3f which was a temporary and quick solution to make the tests succeed again, but which did not solve the problem.
fix #6405 more tests for CdmPermissionVoter.furtherVotingDescisions and fixing the premature returning of DENIED votes made there