build(deps): bump django-downloadview from 2.3.0 to 2.4.0

Bumps [django-downloadview](https://github.com/jazzband/django-downloadview) from 2.3.0 to 2.4.0.
- [Release notes](https://github.com/jazzband/django-downloadview/releases)
- [Changelog](https://github.com/jazzband/django-downloadview/blob/master/CHANGELOG)
- [Commits](jazzband/django-downloadview@2.3.0...2.4.0)

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

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

requirements.txt

@@ -40,7 +40,7 @@ django-mptt==0.16.0
 django-modeltranslation>=0.11,<0.19.0
 django-treebeard==4.7.1
 django-guardian<2.4.1
-django-downloadview==2.3.0
+django-downloadview==2.4.0
 django-polymorphic==3.1.0
 django-tastypie<0.15.0
 django-tinymce==3.7.1