Bump django-stubs from 5.1.1 to 5.1.2

Bumps [django-stubs](https://github.com/typeddjango/django-stubs) from 5.1.1 to 5.1.2.
- [Release notes](https://github.com/typeddjango/django-stubs/releases)
- [Commits](https://github.com/typeddjango/django-stubs/compare/5.1.1...5.1.2

)

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

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