Bump django from 2.2.13 to 2.2.28

Bumps [django](https://github.com/django/django) from 2.2.13 to 2.2.28.
- [Release notes](https://github.com/django/django/releases)
- [Commits](django/django@2.2.13...2.2.28)

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

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

Author: dependabot[bot]

requirements.txt

@@ -43,7 +43,7 @@ decorator==4.4.1
 defusedxml==0.6.0
 Deprecated==1.2.7
 distributed==2.10.0
-Django==2.2.13
+Django==2.2.28
 docker-pycreds==0.4.0
 docutils==0.15.2
 dtale==1.7.15