AWS RDS password rotation with changing username

[thijs]

The PR at #1926 solves part of my problem. In RDS I'm using password rotation with a secondary postgres user, which means that every rotation the username toggles between username and username_clone.

The dynamic password lookup function works, but in my case I need the same for the username, because with the rotation that will have changed as well.

Maybe the separate username and password should also be able to be provided through a credentials object, containing those both, that could be retrieved through a function?

Or am I missing an obvious way to solve this differently?

[thijs]

Added pull request to solve this. See #2682

[thijs]

Is there anything (else) I need to do to get this PR applied? Except wait?