Django 3.2 extended support ends on April 2024 and thus we should upgrade to the next LTS of Django: 4.2

We tried this before and a few libraries had not yet been updated to support 4.2, but have been updated since (namely django_modeltranslations).

Amongst the benefits of running Django 4.2 is the new configuration for storages which will allow us to have a cleaner implementation of multiple storage backends for #865