Bump django from 1.10.3 to 2.2.24 in /requirements

Bumps [django](https://github.com/django/django) from 1.10.3 to 2.2.24.
- [Release notes](https://github.com/django/django/releases)
- [Commits](django/django@1.10.3...2.2.24)

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

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

requirements/base.txt

@@ -4,7 +4,7 @@
 # Verified bug on Python 3.5.1
 boto==2.42.0
 certifi==2017.1.23
-Django==1.10.3
+Django==2.2.24
 django-appconf==1.0.1
 django-autoslug==1.9.3
 django-bmemcached==0.2.3