Rewrite backup and restore roles handling of secrets

[rooftopcellist]

Summary

The galaxy-operator's backup and restore roles handle secrets differently from the other operators. This makes it hard to maintain, and many of the fixes that have been added to the other operators cannot be easily ported here.

We only support restoring from a backup taken by the same version of the operator. So we do not have to try to maintain backwards compatibility in that regard.

We should use awx-operator and the eda-server-operators as models for the pattern for handling secrets.

Additional context
Add any other context about the feature request here.

[rooftopcellist]

It looks like some of the cr_object backup/restore logic was removed in this commit:

• d217cc8

Try to figure out why first.