build(deps): bump prometheus-client from 0.19.0 to 0.20.0

Bumps [prometheus-client](https://github.com/prometheus/client_python) from 0.19.0 to 0.20.0.
- [Release notes](https://github.com/prometheus/client_python/releases)
- [Commits](prometheus/client_python@v0.19.0...v0.20.0)

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

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

requirements.txt

@@ -19,7 +19,7 @@ packaging==23.2
 pandas==2.1.1
 pillow==10.2.0
 prometheus-api-client==0.5.4
-prometheus-client==0.19.0
+prometheus-client==0.20.0
 pydantic==1.10.14
 pydantic-yaml==0.11.2
 pyparsing==3.1.1