Add support for Django 5.2

[jnovinger]

This confirms support for Django 5.2 by modifying the test matrices, classifiers, and documentation alongside currently supported versions 4.2, 5.0, and 5.1.

I did not remove Django 5.0 support yet, even though it stopped being supported on April 2, 2025. I would be happy to add a commit to do so.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 69.74%. Comparing base (0df1039) to head (c46636d).
⚠️ Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #786      +/-   ##
==========================================
- Coverage   74.07%   69.74%   -4.34%     
==========================================
  Files          26       26              
  Lines        1678     1679       +1     
==========================================
- Hits         1243     1171      -72     
- Misses        435      508      +73     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[dulmandakh]

Please fix the CI

[claudep]

I guess we want to first find out why #781 fails.

[jnovinger]

Hey, thanks all! I'm not super-familiar with the individual test that is failing in the [build (3.9, imagemagick)](https://github.com/jazzband/sorl-thumbnail/actions/runs/18288978456/job/52078701622?pr=786#logs) build:

  ======================================================================
  FAIL: test_orientation (tests.thumbnail_tests.test_templatetags.TemplateTestCaseA)
  ----------------------------------------------------------------------
  Traceback (most recent call last):
    File "/home/runner/work/sorl-thumbnail/sorl-thumbnail/tests/thumbnail_tests/test_templatetags.py", line 107, in test_orientation
      self.assertLess(epsilon(left, im.getpixel((7, 14))), 10)
  AssertionError: 62 not less than 10

Any guidance you can provide?

I also can't reproduce this on my local (Mac OS 15.6.1 w/ ImageMagick v7.x, versus the v6.9.12.98 which seems to be being run in Ubuntu 24.04 in Github Actions). I'm working on trying to reproduce via a Docker image, but that is not going quickly.

[jnovinger]

I just realized neither of approaches to fixing the CI failures is likely to work as described in the commit message of c46636d above, because the tests are shared across all backends but giving one backend a setting change that affect cache key values will now break tests in other backends. I think.

I would definitely welcome feedback here on how to handle this.

[jnovinger]

@dulmandakh, based on my commit message and comment above, as well as @claudep's point about #781, I think we can all agree this is a pre-existing issue to this PR.

Looking at the CI status for the second commit (which does fix some CI issues), you can see that only the ImageMagick related tests are failing. I'd be happy to remove my follow up attempt commit to fix the remaining CI issues and create a new bug issue for it.