build(deps-dev): bump urllib3 from 1.26.14 to 1.26.15 (#550)

Bumps [urllib3](https://github.com/urllib3/urllib3) from 1.26.14 to 1.26.15.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/main/CHANGES.rst)
- [Commits](urllib3/urllib3@1.26.14...1.26.15)

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

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

Author: dependabot[bot]

demos/moderator_bot/requirements-dev.txt

@@ -20,6 +20,6 @@ scikit-learn==0.21.3
 scipy==1.9.3
 six==1.16.0
 slacker==0.9.42
-urllib3==1.26.14
+urllib3==1.26.15
 yarl==1.8.2
 zipp==3.15.0