fix: allow backup verification and restore to work with patroni

[thegentlemanphysicist]

This drops the metric helpers and user management schemas used by patroni, allowing the backup container to verify and restore patroni stateful sets (using postgres 13 server specifically).
Note the -I flag is still needed for these to work: /backup.sh -I -r <databaseSpec/>

and

./backup.sh -I -v all

To validate the db.