Drop Python 3.8 & add official support for Python 3.13 & Django 5.1

[samiashi]

https://devguide.python.org/versions/
https://endoflife.date/django

[katiam2]

@samiashi could you please re-base your brunch against main to include the latest fixes that allow builds to trigger

[samiashi]

@katiam2 I've rebased now

Is the (3.12) failure expected?

coveralls-django4.2-python3.12: commands[4]> coveralls
  Error running coveralls: Not on TravisCI. You have to provide either repo_token in .coveralls.yml or set the COVERALLS_REPO_TOKEN env var.
  Traceback (most recent call last):
    File "/home/runner/work/django-jazzmin/django-jazzmin/.tox/coveralls-django4.2-python3.12/lib/python3.12/site-packages/coveralls/cli.py", line 65, in main
      coverallz = Coveralls(
                  ^^^^^^^^^^
    File "/home/runner/work/django-jazzmin/django-jazzmin/.tox/coveralls-django4.2-python3.12/lib/python3.12/site-packages/coveralls/api.py", line 47, in __init__
      self.ensure_token()
    File "/home/runner/work/django-jazzmin/django-jazzmin/.tox/coveralls-django4.2-python3.12/lib/python3.12/site-packages/coveralls/api.py", line 60, in ensure_token
      raise CoverallsException(
  coveralls.exception.CoverallsException: Not on TravisCI. You have to provide either repo_token in .coveralls.yml or set the COVERALLS_REPO_TOKEN env var.

[katiam2]

@samiashi it seems that test coverage tool's token has expired. We can merge without it for now. I’ll do some visual checks and try to get this merged soon.

[farridav]

we will resolve coveralls issue in a follow up PR, thanks for the contribution !!