Bump urllib3 from 1.26.17 to 1.26.18

Bumps [urllib3](https://github.com/urllib3/urllib3) from 1.26.17 to 1.26.18.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/main/CHANGES.rst)
- [Commits](urllib3/urllib3@1.26.17...1.26.18)

---
updated-dependencies:
- dependency-name: urllib3
  dependency-type: direct:production
...

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

requirements.txt

@@ -19,6 +19,6 @@ python-dotenv==0.17.0
 pytz==2021.3
 six==1.15.0
 typing-extensions==3.7.4.3
-urllib3==1.26.17
+urllib3==1.26.18
 yarl==1.6.3
 termcolor==2.0.1