chore(deps): bump urllib3 in /backend/requirements

Bumps [urllib3](https://github.com/urllib3/urllib3) from 1.26.18 to 1.26.19.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/1.26.19/CHANGES.rst)
- [Commits](urllib3/urllib3@1.26.18...1.26.19)

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

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

backend/requirements/dev.txt

@@ -160,7 +160,7 @@ typing-extensions==3.10.0.2
     # via
     #   astroid
     #   pylint
-urllib3==1.26.18
+urllib3==1.26.19
     # via
     #   requests
     #   sentry-sdk

backend/requirements/prod.txt

@@ -95,7 +95,7 @@ tqdm==4.66.3
     # via -r requirements.in/base.txt
 typing-extensions==4.6.3
     # via asgiref
-urllib3==2.1.0
+urllib3==1.26.19
     # via
     #   requests
     #   sentry-sdk