Update django-linear-migrations requirement

Updates the requirements on [django-linear-migrations](https://github.com/adamchainz/django-linear-migrations) to permit the latest version.
- [Changelog](https://github.com/adamchainz/django-linear-migrations/blob/main/CHANGELOG.rst)
- [Commits](adamchainz/django-linear-migrations@2.8.0...2.13.0)

---
updated-dependencies:
- dependency-name: django-linear-migrations
  dependency-type: direct:production
...

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

requirements.txt

@@ -10,7 +10,7 @@ django-rest-passwordreset>=1.1,<1.5
 drf-spectacular[sidecar]>=0.26.2,<0.28
 django-environ>=0.10.0,<0.12
 django-gravatar2>=1.4.4,<1.5
-django-linear-migrations>=2.8.0,<2.13
+django-linear-migrations>=2.8.0,<2.14
 pytest-django>=4.5.2,<4.7
 pytest-cov>=4.1.0,<5.1
 sentry-sdk>=2.9.0,<2.10