Fix tests in ``utests/ManagedRepositoryITest``

This PR cleans up the test class and removes tests related to path conflict resolution. Methods from ManagedRepositoryI aren't easy to unit test - there is a refactoring pending after which the test class can be updated.

To test, execute ``./build.py -f components/blitz/build.xml test -DTEST=ome/services/blitz/test/utests/ManagedRepositoryITest``. No failures should be present.

This needs #1141 for testing.