[Enhancement] Allow some kind of Vault integration

[mrkwtz]

Hey there,

we would really like to integrate Vault for managing the pgbackrest encryption passphrase. Unfortunately for now there is no way one could do that. The easiest fix would be to allow spec.args/command changes in the Helm chart for the pgbackrest container to mount an environment file via Vault und source them before starting the python script that is handling the backups.

Other ways would be to extend the python script to allow for any kind of Vault integration but I guess that would need more effort.

Have a nice weekend!