change default mysql_native_password to caching_sha2_password
From MySQL 8.0.34
The mysql_native_password authentication plugin now is deprecated and subject to removal in a future version of MySQL. CREATE USER, ALTER USER, and SET PASSWORD operations now insert a deprecation warning into the server error log if an account attempts to authenticate using mysql_native_password as an authentication method. (Bug #35336317)
I think it is only https://gitlab.com/allianceauth/allianceauth/-/blame/master/docker/docker-compose.yml?ref_type=heads#L6 that needs changing in a new install, if all clients are MySQL 8 compatible or better.