Bump gunicorn from 20.1.0 to 22.0.0 in /app/frontend

Bumps [gunicorn](https://github.com/benoitc/gunicorn) from 20.1.0 to 22.0.0.
- [Release notes](https://github.com/benoitc/gunicorn/releases)
- [Commits](benoitc/gunicorn@20.1.0...22.0.0)

---
updated-dependencies:
- dependency-name: gunicorn
  dependency-type: direct:production
...

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

Author: dependabot[bot]

app/frontend/requirements.txt

@@ -6,6 +6,6 @@ flask-cors==4.0.0; python_version >= "3.7"
 pika==1.3.0; python_version >= "3.7"
 prometheus-client==0.16.0; python_version >= "3.7"
 requests==2.31.0; python_version >= "3.7"
-gunicorn==20.1.0; python_version >= "3.7"
+gunicorn==22.0.0; python_version >= "3.7"
 flask-prometheus-metrics==1.0.0; python_version >= "3.7"
 python-json-logger==2.0.7; python_version >= "3.7"