Bump requests from 2.19.1 to 2.20.0 in /News Chatbot

Bumps [requests](https://github.com/requests/requests) from 2.19.1 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@v2.19.1...v2.20.0)

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

Author: dependabot[bot]

News Chatbot/requirements.txt

@@ -8,7 +8,7 @@ itsdangerous==0.24
 Jinja2==2.10
 MarkupSafe==1.0
 pymessenger==0.0.7.0
-requests==2.19.1
+requests==2.20.0
 requests-toolbelt==0.8.0
 six==1.11.0
 urllib3==1.24.2