Comment 4 for bug 1915740

The change has broken users at least cinder-backup, which uses swift, and tempest tests for volume backup can't access swift anymore.

Now we have a problem: each job can override tempest_roles. But if that's done through zuul configuration, which means local.conf, those values override any existing value. This breaks for example the barbican tempest plugin which takes care of adding an item to the list, and users can't rely on this anymore.