Bump django-stubs-ext from 0.5.0 to 4.2.7

Bumps [django-stubs-ext](https://github.com/typeddjango/django-stubs) from 0.5.0 to 4.2.7.
- [Release notes](https://github.com/typeddjango/django-stubs/releases)
- [Commits](https://github.com/typeddjango/django-stubs/compare/django-stubs-ext@0.5.0...4.2.7)

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

Signed-off-by: dependabot[bot] <support@github.com>

requirements-test.txt

@@ -5,4 +5,4 @@ mypy==0.982
 psycopg2-binary==2.9.4
 Django==4.1.2
 django-stubs==1.12.0
-django-stubs-ext==0.5.0
+django-stubs-ext==4.2.7