8c708b Change database url from postgres: to postgresql:

Authored and Committed by Christian Boltz a year ago
    Change database url from postgres: to postgresql:
    
    This is needed to give us a working mailman even with the latest updates
    installed.
    
    This is copy&paste from stackoverflow, which says on
    https://stackoverflow.com/questions/62688256/sqlalchemy-exc-nosuchmoduleerror-cant-load-plugin-sqlalchemy-dialectspostgre
    
        The URI should start with postgresql:// instead of postgres://.
        SQLAlchemy used to accept both, but has removed support for the
        postgres name.