Bump django-extensions from 3.0.3 to 3.0.4 in /cvat/requirements (#1993)

Bumps [django-extensions](https://github.com/django-extensions/django-extensions) from 3.0.3 to 3.0.4.
- [Release notes](https://github.com/django-extensions/django-extensions/releases)
- [Changelog](https://github.com/django-extensions/django-extensions/blob/master/CHANGELOG.md)
- [Commits](https://github.com/django-extensions/django-extensions/compare/3.0.3...3.0.4)

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

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

cvat/requirements/development.txt

@@ -8,6 +8,6 @@ pylint-django==2.2.0
 pylint-plugin-utils==0.6
 rope==0.17.0
 wrapt==1.12.1
-django-extensions==3.0.3
+django-extensions==3.0.4
 Werkzeug==1.0.1
 snakeviz==2.1.0