In short, the problem is that older Postgres versions store passwords
hashed as md5. When you dump such a database, the dump naturally also
contains md5-hashed passwords.
Restoring from that dump used to create users and updates their passwords
with these md5 hashes.
However, Postgres v14 prefers does not like md5-hashed passwords now (by default),
which breaks connectivity. Postgres v14 prefers `scram-sha-256` for
authentication.

Our solution is to just ignore setting passwords (`ALTER ROLE ..`
statements) when restoring dumps. We don't need to set passwords as
defined in the dump anyway, because the playbook creates users
and manages their passwords by itself.

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1340