Bump prometheus-client from 0.17.1 to 0.18.0

Bumps [prometheus-client](https://github.com/prometheus/client_python) from 0.17.1 to 0.18.0.
- [Release notes](https://github.com/prometheus/client_python/releases)
- [Commits](prometheus/client_python@v0.17.1...v0.18.0)

---
updated-dependencies:
- dependency-name: prometheus-client
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

requirements.txt

@@ -7,4 +7,4 @@ python-json-logger==2.0.7
 requests==2.31.0
 sentry-sdk==0.19.5
 watchtower==3.0.1
-prometheus_client==0.17.1
+prometheus_client==0.18.0