chore(deps): bump urllib3 in /backend in the python group (#608)

Bumps the python group in /backend with 1 update: [urllib3](https://github.com/urllib3/urllib3).


Updates `urllib3` from 2.2.2 to 2.2.3
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/main/CHANGES.rst)
- [Commits](urllib3/urllib3@2.2.2...2.2.3)

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

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

backend/requirements.txt

@@ -67,7 +67,7 @@ tzdata==2023.3
     # via pytz-deprecation-shim
 tzlocal==5.0.1
     # via apscheduler
-urllib3==2.2.2
+urllib3==2.2.3
     # via -r requirements.in
 whitenoise==6.7.0
     # via -r requirements.in