Bump django-model-utils from 4.2.0 to 4.3.1

Bumps [django-model-utils](https://github.com/jazzband/django-model-utils) from 4.2.0 to 4.3.1.
- [Release notes](https://github.com/jazzband/django-model-utils/releases)
- [Changelog](https://github.com/jazzband/django-model-utils/blob/master/CHANGES.rst)
- [Commits](jazzband/django-model-utils@4.2.0...4.3.1)

---
updated-dependencies:
- dependency-name: django-model-utils
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

requirements/base.txt

@@ -12,7 +12,7 @@ oauthlib==3.2.1  # https://github.com/oauthlib/oauthlib
 django==3.2.16  # pyup: < 3.3  # https://www.djangoproject.com/
 django-environ==0.8.1  # https://github.com/joke2k/django-environ
 django-maintenance-mode==0.16.3 # https://github.com/fabiocaccamo/django-maintenance-mode
-django-model-utils==4.2.0  # https://github.com/jazzband/django-model-utils
+django-model-utils==4.3.1  # https://github.com/jazzband/django-model-utils
 django-allauth==0.51.0  # https://github.com/pennersr/django-allauth
 django-crispy-forms==1.14.0  # https://github.com/django-crispy-forms/django-crispy-forms
 django-redis==5.2.0  # https://github.com/jazzband/django-redis