Replace postgres: by postgresql: for database_url

[stweil]

The latest versions of SQLAlchemy no longer support "postgres:".
That old URL form was deprecated more than 10 years ago:

https://github.com/sqlalchemy/sqlalchemy/blob/8fc5005dfe3eb66a46470ad8a8c7b95fc4d6bdca/lib/sqlalchemy/dialects/postgres.py

Signed-off-by: Stefan Weil sw@weilnetz.de

[stweil]

See also sqlalchemy/sqlalchemy#6083 (comment).

There are also some files which use SQLite (sqlite:///) instead of PostgreSQL. Which database software is preferred? Should both work?

Perhaps the code could use database_url = args.database, so the database argument would provide the full URL and the user were free to choose either SQLite or PostgreSQL.