Upgrade to Django 4.2 - Githubissues

Checklist to prepare the Django 4.2 LTS upgrade

3rd party packages to verify/make compatible

[ ] commonground-api-common - needs 4.2 support, and depends on drf-yasg etc. which is problematic
[x] django-admin-index - ok
[ ] django-axes
- version is okay
- however, it is not specified as django-axes[ipware] so ipware is not pulled in, yet there are settings referring to ipware
- possibly the reverse proxy setup is broken to determine the IP address because of this
- it also uses legacy django axes settings like AXES_LOCK_OUT_BY_COMBINATION_USER_AND_IP
- might just not be working properly at all
[ ] django-better-admin-arrayfield -> needs to be replaced, see https://github.com/open-formulieren/open-forms/pull/3737 for the involved changes
[x] django-cors-headers - ok
[ ] django-db-logger - uncertain, does not appear to be tested on Django newer than 3.2 but latest release was end of 2023
[ ] django-loose-fk - no support, but seems to be scheduled for removal in #128
[x] django-markup - ok
[x] django-redis - ok
[x] django-rosetta - ok
[ ] djangorestframework - 3.14 added support for Django 4.1, 4.2 should work too (according to Github)
- this also massively affects drf-yasg, which is being removed in favour of spectacular in #120
- switch to spectacular may upgrade this from 3.12 to 3.14
[x] elastic-apm - ok
[ ] mozilla-django-oidc-db - requires v0.14.0, see also #129
[x] psycopg2 - current version is supported, upgrading to psycopg 3 is viable though
[x] sentry_sdk - ok
[x] zgw-consumers - ok

3rd party packages (planned) to be dropped?

[ ] click - doesn't seem to be used anywhere
[ ] jq - doesn't seem to be used anywhere
[ ] jsonschema - doesn't seem to be used anywhere
[ ] dictdiffer - doesn't seem to be used anywhere
[ ] python-dateutil - doesn't seem to be used anywhere
[ ] requests - used by third party packages, but no direct usage -> can be removed from base.in
[ ] requests-cache - doesn't seem to be used anywhere
[ ] self-certifi - doesn't seem to be used
[ ] bleach - doesn't seem to be used
[ ] django-extra-views - doesn't seem to be used
[x] django-log-outgoing-requests - ok but doesn't seem to be used
[ ] django-sniplates - dead code only it seems

Open Klant itself

[ ] src/openklant/scss/admin/admin_overrides.scss does not yet make use of the CSS variables for colors, which will lead to (likely) unusable dark theme
- a better but incomplete setup can be taken from OF
- https://github.com/open-formulieren/open-forms/blob/master/src/openforms/scss/admin/_app_overrides.scss#L11
- https://github.com/open-formulieren/open-forms/blob/master/src/openforms/scss/admin/_admin_theme.scss#L59
- these admin overrides need a revisit anyway and probably we should check what the state of them is in default-project
[x] Did not find any usage of removed ugettext* functions

maykinmedia / open-klant