No use of mox/mox3

Now onwards no support of mox/mox3, please check storyboard link
for reference

https://storyboard.openstack.org/#!/story/2001546

Change-Id: Ic1fa65951f1e43e1279d8c72fcfc5e09609faa70

tests/clients.py

@@ -61,7 +61,7 @@ class KeystoneClient(OpenStackClients):
 
 
 if __name__ == '__main__':
-    # TODO(Jeff Peeler): mox this
+    # TODO(Jeff Peeler): mock this
     client_mgr = OpenStackClients()
     ks = client_mgr.get_client('KeystoneClient')
     LOG.info(ks)