build(deps): bump urllib3 from 1.26.8 to 1.26.9

Bumps [urllib3](https://github.com/urllib3/urllib3) from 1.26.8 to 1.26.9.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/1.26.9/CHANGES.rst)
- [Commits](https://github.com/urllib3/urllib3/compare/1.26.8...1.26.9)

---
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

@@ -73,7 +73,7 @@ tlslite-ng==0.7.6
 tweepy==4.6.0
 ujson==5.1.0
 update-checker==0.18.0
-urllib3==1.26.8
+urllib3==1.26.9
 webapp2==3.0.0b1
 webencodings==0.5.1
 WebOb==1.8.7