Bump django from 2.1.11 to 2.2.27

Bumps [django](https://github.com/django/django) from 2.1.11 to 2.2.27.
- [Release notes](https://github.com/django/django/releases)
- [Commits](django/django@2.1.11...2.2.27)

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

Signed-off-by: dependabot[bot] <[email protected]>

requirements.txt

@@ -1,7 +1,7 @@
 certifi==2018.11.29
 chardet==3.0.4
 coverage==4.5.2
-Django==2.1.11
+Django==2.2.27
 googlemaps==3.0.2
 idna==2.8
 pytz==2018.7