'juju create-backup' should give feedback about what it is doing

[John A Meinel]

When you initiate `juju create-backup` it starts processing, but it doesn't tell you something reassuring like:

Backing up the controller to juju-2022-02-02.tgz

And then some sort of progress messages from the controller indicating where it is at around the backup progress. Right now on a large controller you initiate the process and then just wait, and there isn't any reassurance that you are doing what you asked. And it takes long enough to make you worry.

[Canonical Juju QA Bot (juju-qa-bot)]

This Medium-priority bug has not been updated in 60 days, so we're marking it Low importance. If you believe this is incorrect, please update the importance.