Bump django-stubs from 1.12.0 to 4.2.0

Bumps [django-stubs](https://github.com/typeddjango/django-stubs) from 1.12.0 to 4.2.0.
- [Release notes](https://github.com/typeddjango/django-stubs/releases)
- [Commits](https://github.com/typeddjango/django-stubs/compare/django-stubs@1.12.0...4.2.0)

---
updated-dependencies:
- dependency-name: django-stubs
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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