Bump the python-dependencies group with 3 updates

Bumps the python-dependencies group with 3 updates: [httpx](https://github.com/encode/httpx), [django](https://github.com/django/django) and [coverage](https://github.com/nedbat/coveragepy).


Updates `httpx` from 0.28.0 to 0.28.1
- [Release notes](https://github.com/encode/httpx/releases)
- [Changelog](https://github.com/encode/httpx/blob/master/CHANGELOG.md)
- [Commits](encode/httpx@0.28.0...0.28.1)

Updates `django` from 5.1.3 to 5.1.4
- [Commits](django/django@5.1.3...5.1.4)

Updates `coverage` from 7.6.8 to 7.6.9
- [Release notes](https://github.com/nedbat/coveragepy/releases)
- [Changelog](https://github.com/nedbat/coveragepy/blob/master/CHANGES.rst)
- [Commits](nedbat/coveragepy@7.6.8...7.6.9)

---
updated-dependencies:
- dependency-name: httpx
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: python-dependencies
- dependency-name: django
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: python-dependencies
- dependency-name: coverage
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: python-dependencies
...

Signed-off-by: dependabot[bot] <[email protected]>