Update prometheus-client requirement from ~=0.22.1 to ~=0.23.1

Updates the requirements on [prometheus-client](https://github.com/prometheus/client_python) to permit the latest version.
- [Release notes](https://github.com/prometheus/client_python/releases)
- [Commits](prometheus/client_python@v0.22.1...v0.23.1)

---
updated-dependencies:
- dependency-name: prometheus-client
  dependency-version: 0.23.1
  dependency-type: direct:production
...

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

Author: dependabot[bot]

setup/requirements.txt

@@ -6,5 +6,5 @@ requests
 pytz
 aiohttp~=3.12.7
 discordhealthcheck~=0.1.1
-prometheus_client~=0.22.1
+prometheus_client~=0.23.1
 pyyaml~=6.0