Bump django from 3.0.9 to 3.1

Bumps [django](https://github.com/django/django) from 3.0.9 to 3.1.
- [Release notes](https://github.com/django/django/releases)
- [Commits](https://github.com/django/django/compare/3.0.9...3.1)

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

requirements.txt

@@ -1,5 +1,5 @@
 asgiref==3.2.10
-Django==3.0.9
+Django==3.1
 pytz==2020.1
 sqlparse==0.3.1
 requests