Bump celery-redbeat from 2.2.0 to 2.3.2 in /server (#246)

Bumps [celery-redbeat](https://github.com/sibson/redbeat) from 2.2.0 to 2.3.2.
- [Release notes](https://github.com/sibson/redbeat/releases)
- [Changelog](https://github.com/sibson/redbeat/blob/main/CHANGES.txt)
- [Commits](sibson/redbeat@v2.2.0...v2.3.2)

---
updated-dependencies:
- dependency-name: celery-redbeat
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

server/requirements.txt

@@ -50,7 +50,7 @@ celery[redis]==5.4.0
     # via
     #   celery-redbeat
     #   superdesk-core
-celery-redbeat==2.2.0
+celery-redbeat==2.3.2
     # via -r requirements.in
 cerberus==1.3.5
     # via