We need to point at the new discourse.py, not at the automail.py that
no longer exists.

Also, reformat it a bit to be shorter.

The create_discourse_post function is lifted from here:
https://gitlab.gnome.org/Infrastructure/openshift-images/accounts-automation-app/-/blob/main/app/cronjobs/new_members_digest.py?ref_type=heads

It didn't build, and I didn't want to spend time thinking about it.

This will prevent Discourse from blocking the reminder if the topic
exactly matches a previous topic.

I attempted to change the From address, but this broke the automatic
mails as Discourse expects them to come from releng@gnome.org. Then I
attempted to revert back to releng@gnome.org, but missed a spot. Andrea
says this is causing the mails to be rejected. Oops.

wiki.gnome.org is being decommissioned.

Of course, most of these links are actually only used when generating
the schedule wiki page, which will no longer happen, but this is step
one to replacing that with something newer. And one of the links is used
in our release reminders, which is definitely worth replacing now.

This reverts commit 9199c490.

This caused Discourse to start rejecting our mails. It's OK to use a
fake sender address for this mail because it should be seen only by
Discourse and not by end users.

This address is no longer monitored

There are excessive downtime/reliability issues with cairographics.org
so we cannot depend on it anymore. These tarballs will need to be
updated manually.

This should be removed when gi-docgen#179 is fixed. Until then, let's
downgrade the stable runtimes to the last good version 2023.1.

corresponds with
gnome-build-meta@ef8e01d1