Bump requests from 2.2.1 to 2.20.0

Bumps [requests](https://github.com/psf/requests) from 2.2.1 to 2.20.0.
- [Release notes](https://github.com/psf/requests/releases)
- [Changelog](https://github.com/psf/requests/blob/main/HISTORY.md)
- [Commits](psf/requests@v2.2.1...v2.20.0)

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

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

Author: dependabot[bot]

requirements.txt

@@ -31,7 +31,7 @@ pyserial==2.6
 python-apt==0.9.3.5ubuntu2
 python-debian==0.1.21-nmu2ubuntu2
 pytz==2016.4
-requests==2.2.1
+requests==2.20.0
 roman==2.0.0
 six==1.5.2
 ssh-import-id==3.21