Bump python-telegram-bot from 20.7 to 20.8

Bumps [python-telegram-bot](https://github.com/python-telegram-bot/python-telegram-bot) from 20.7 to 20.8.
- [Release notes](https://github.com/python-telegram-bot/python-telegram-bot/releases)
- [Changelog](https://github.com/python-telegram-bot/python-telegram-bot/blob/master/CHANGES.rst)
- [Commits](python-telegram-bot/python-telegram-bot@v20.7...v20.8)

---
updated-dependencies:
- dependency-name: python-telegram-bot
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

requirements.txt

@@ -18,7 +18,7 @@ protobuf==4.25.2
 pyasn1==0.5.1
 pyasn1-modules==0.3.0
 python-dotenv==1.0.1
-python-telegram-bot==20.7
+python-telegram-bot==20.8
 requests==2.31.0
 rsa==4.9
 sniffio==1.3.0