Bump django from 3.1.5 to 3.1.12

Bumps [django](https://github.com/django/django) from 3.1.5 to 3.1.12.
- [Release notes](https://github.com/django/django/releases)
- [Commits](https://github.com/django/django/compare/3.1.5...3.1.12

)

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

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

requirements.txt

@@ -4,7 +4,7 @@ async-timeout==3.0.1
 attrs==20.3.0
 certifi==2020.12.5
 chardet==3.0.4
-Django==3.1.5
+Django==3.1.12
 idna==2.10
 multidict==5.1.0
 python-dotenv==0.15.0