Replace assertEqual(None, *) with assertIsNone in tests
Replace assertEqual(None, *) with assertIsNone in tests

Replace assertEqual(None, *) with assertIsNone in tests to have
more clear messages in case of failure.

Change-Id: I9410018cada9503accd6191cfdd3f12ab1c8ba3d
Closes-bug: #1280522

sniperganso/python-manilaclient,sniperganso/python-manilaclient