Bump gunicorn from 19.9.0 to 23.0.0

Bumps [gunicorn](https://github.com/benoitc/gunicorn) from 19.9.0 to 23.0.0.
- [Release notes](https://github.com/benoitc/gunicorn/releases)
- [Commits](benoitc/gunicorn@19.9.0...23.0.0)

---
updated-dependencies:
- dependency-name: gunicorn
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

requirements.txt

@@ -1,7 +1,7 @@
 flask==2.0.3
 werkzeug==2.0.3
 requests==2.20.0
-gunicorn==19.9.0
+gunicorn==23.0.0
 gevent==1.3.7
 cachetools==2.1.0
 pymongo==4.7.2