Django4 compatibility and some legacy cleanup

[geophphrie]

• Eliminated providing_args in Signal()
• Fixed urls to use re_path()
• Eliminated mock, future, six
• Fixed settings (used for testing) to be Dj4 compatible
• Added warnings to manage.py
• Squashed migrations
• Implemented github actions testing
• Set to a beta version for now.

The only thing remaining here to resolve is the usage of ambition-django-uuidfield. Not sure the plan for that.

[somewes]

it looks like this depends on ambition-django-uuidfield, which hasn't been kept up to date in our spreadsheet. i'd like to see if we can get rid of our custom uuid field package and do something like we did with the timezone field. rather than maintaining a whole package to make a small change, we can just extend the field class in ambition-utils to add any extra logic there. i don't know what custom functionality is needed there if any.

[geophphrie]

That sounds good @somewes . At the very moment I'm doing a search-and-destroy purely on hard incompatibilities with Django 4. I.e. I have upgraded a local system to Dj4 and am seeing what breaks just trying to do a python manage.py check Some of these fixes are pretty low hanging fruit. If I get them out of the way it will be easier to see what other work might need to be done. But stuff like uuidfield and timezone will be great to abstract out in a better way and fix across the board.

[somewes]

removed the uuid field dependency since it is built into django and was switched in 2017