build(deps): bump django-model-utils from 4.3.1 to 4.5.1 (#1614)

Bumps [django-model-utils](https://github.com/jazzband/django-model-utils) from 4.3.1 to 4.5.1.
- [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@4.3.1...4.5.1)

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

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

docs_manual/requirements.txt

@@ -49,7 +49,7 @@ django-environ==0.11.2
 django-extensions==3.2.3
 django-iconify==0.1.1
 django-markupfield==2.0.1
-django-model-utils==4.3.1
+django-model-utils==4.5.1
 django-pagedown==2.2.1
 django-plugins-bihealth==0.4.0
 django-postgres-copy==2.3.7