Bump urllib3 from 1.26.5 to 1.26.6

Bumps [urllib3](https://github.com/urllib3/urllib3) from 1.26.5 to 1.26.6.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/1.26.6/CHANGES.rst)
- [Commits](https://github.com/urllib3/urllib3/compare/1.26.5...1.26.6)

---
updated-dependencies:
- dependency-name: urllib3
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

requirements.txt

@@ -10,7 +10,7 @@ python-telegram-bot==13.6
 arrow==1.1.1
 cachetools==4.2.2
 requests==2.25.1
-urllib3==1.26.5
+urllib3==1.26.6
 wrapt==1.12.1
 jsonschema==3.2.0
 TA-Lib==0.4.20