0.4.0 feature release

This release integrates all of the bugfixes and features of the 0.3 release, and adds support for Django 4.0. We still recommend using Django 3.2 LTS for stability, but early adopters may of course now start using Django 4. We will continue updating django-helpdesk version 0.4 with bugfixes until Django 4.2 LTS is released, to ensure that all users have a smooth migration path.

We do not expect many new features in the 0.4 release series for this reason, since we're mostly doing Django 4 support and cleanups. New features are targeted for the 0.5 release, release date TBD.