Rotation of user passwords

[Cyper-Madsen]

To support most enterprise eployments and requirements in post security standards like ISO27000, the operator should support password rotation, and as the username have a random generated suffix it could be implemented in the same way as the postgresql operator from Zalando is doing it description

In general terms the rotations creates a new user every <password_rotation_interval> days with the same permissions as previous user and updated the secret with the new credentials, when creating the new user it checks all previous created users and delete all the users that are older then <password_rotation_user_retention>days.