Bump django-anymail[mailgun] from 11.1 to 12.0

Bumps [django-anymail[mailgun]](https://github.com/anymail/django-anymail) from 11.1 to 12.0.
- [Release notes](https://github.com/anymail/django-anymail/releases)
- [Changelog](https://github.com/anymail/django-anymail/blob/main/CHANGELOG.rst)
- [Commits](anymail/django-anymail@v11.1...v12.0)

---
updated-dependencies:
- dependency-name: django-anymail[mailgun]
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

requirements.txt

@@ -5,7 +5,7 @@ crispy-bootstrap5==2024.2
 django==4.2.15
 django-allauth==64.2.0
 django-allauth[mfa]==64.2.0
-django-anymail[mailgun]==11.1
+django-anymail[mailgun]==12.0
 django-braces==1.15.0
 django-cjswidget==0.4.1
 django-cleanup==8.1.0