Bump requests from 2.3.0 to 2.20.0

Bumps [requests](https://github.com/requests/requests) from 2.3.0 to 2.20.0.
- [Release notes](https://github.com/requests/requests/releases)
- [Changelog](https://github.com/psf/requests/blob/master/HISTORY.md)
- [Commits](psf/requests@v2.3.0...v2.20.0)

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

requirements.txt

@@ -12,5 +12,5 @@ django-q==0.8.0
 docutils==0.11
 openpyxl==2.4.1
 redis==2.10.5
-requests==2.3.0
+requests==2.20.0
 wsgiref==0.1.2