Comment 3 for bug 1945239

This is actually too drastic change from a charm ecosystem point of view and will break a backward compatibility although the patch itself is in a good intention and nothing is wrong from an upstream config point of view.

I'd really like to see the follow-up change gets merged before the change gets into stable as a part of 21.10 release.
https://review.opendev.org/c/openstack/charm-cinder/+/814845