chore(deps): bump django from 1.11.29 to 2.2.24 in /requirements

Bumps [django](https://github.com/django/django) from 1.11.29 to 2.2.24.
- [Release notes](https://github.com/django/django/releases)
- [Commits](django/django@1.11.29...2.2.24)

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

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

Author: dependabot[bot]

requirements/base.txt

@@ -1,6 +1,6 @@
 celery==4.0.0
 dj-database-url==0.4.1
-Django==1.11.29
+Django==2.2.24
 django-bootstrap-pagination==1.6.2
 django-bootstrap3==11.0.0
 django-braces==1.11.0