Bump requests from 2.11.1 to 2.20.0

Bumps [requests](https://github.com/requests/requests) from 2.11.1 to 2.20.0.
- [Release notes](https://github.com/requests/requests/releases)
- [Changelog](https://github.com/psf/requests/blob/master/HISTORY.md)
- [Commits](https://github.com/requests/requests/compare/v2.11.1...v2.20.0)

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

requirements.txt

@@ -21,7 +21,7 @@ pycurl==7.43.0
 pyOpenSSL==17.5.0
 pytz==2016.10
 pyxdg==0.26
-requests==2.11.1
+requests==2.20.0
 scour==0.32
 six==1.10.0
 urllib3==1.24.2