Bump rsa from 3.4.2 to 4.7

Bumps [rsa](https://github.com/sybrenstuvel/python-rsa) from 3.4.2 to 4.7.
- [Release notes](https://github.com/sybrenstuvel/python-rsa/releases)
- [Changelog](https://github.com/sybrenstuvel/python-rsa/blob/main/CHANGELOG.md)
- [Commits](sybrenstuvel/python-rsa@version-3.4.2...version-4.7)

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

Author: dependabot[bot]

requirements.txt

@@ -15,7 +15,7 @@ pyasn1==0.4.3
 python-telegram-bot==10.1.0
 PyYAML==3.12
 requests==2.20.0
-rsa==3.4.2
+rsa==4.7
 six==1.11.0
 urllib3==1.22
 virtualenv==16.0.0