Declaring support for Django 5.0 (and Python 3.12)?

[jonafato]

djangorestframework-api-key currently declares Django 4.2 and Python 3.11 as the latest supported versions. Aside from an easily fixable test failure (details below), a local pytest run suggests that everything works on Django 5.0 and Python 3.12. I'd be happy to submit a PR for these minor changes.

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Details of minor test failures: three parametrized tests (tests/test_model.py::test_has_expired) fail with the following type error:

TypeError: can't compare offset-naive and offset-aware datetimes

This error is rooted in a change to the default behavior of the USE_TZ setting in 5.0. Based on Django's own defaults and recommendations, changing to use timezones by default (in conftest.py and dateutils.py) seems reasonable, but setting USE_TZ to False also gets tests passing consistently across versions.

[florimondmanca]

Hi there!

Vert happy to review a PR indeed. In most cases these version support bumps have been mostly painless.