
Instead of using long backend/drivers name, use short name and stevedore will load plugins for us. It will prevent this kind of message in logs: Failed to load 'keystone.catalog.backends.sql.Catalog' using stevedore: No 'keystone.catalog' driver found, Also cleanup unit and functional tests that were setting wrong credential & assignment drivers. Change-Id: Id3b8ed63ef9a821eba5374af7ed0fd1c8d755e09