Updated openstack/openstack
Project: openstack/keystone  61ccca516c38a51fb14437b94914fc417d497f96

wrong logic in assertValidRoleAssignmentListResponse method

According to current logic, we always use the last of entities to
compare with ref. And, actually, we provide another method
assertRoleAssignmentInListResponse to judge whether the ref in the
list. So, the ref parameter could be removed.

Change-Id: I3f8786baa6964c0f17add2d669aa736732698ea7