What is the recommended Mailman3 web cron job configuration under Debian?

The [Mailman3 web installation instructions](https://docs.mailman3.org/en/latest/config-web.html#scheduled-tasks-required) ask for the configuration of various cron jobs. This is not specified in the [Debian Mailman3 installation instructions](https://salsa.debian.org/mailman-team/mailman-suite/-/blob/master/debian/README.Debian) , which might suggest that the Debian mailman3-full package sets up what is required. Yet no cron jobs are listed in /var/spool/cron/crontabs/. In addition, trying to run the specified jobs from the command line (e.g. sudo -u list mailman /usr/bin/mailman-web runjobs hourly) results in the error: ValueError: Language code already registered: ar.