Bump django from 2.2.19 to 2.2.24

Bumps [django](https://github.com/django/django) from 2.2.19 to 2.2.24.
- [Release notes](https://github.com/django/django/releases)
- [Commits](https://github.com/django/django/compare/2.2.19...2.2.24

)

---
updated-dependencies:
- dependency-name: django
  dependency-type: direct:production
...

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

requirements.txt

-Django==2.2.19
+Django==2.2.24
 django_webtest>=1.9.7
 
 gunicorn==20.0.4