Bump gunicorn from 20.1.0 to 23.0.0

Bumps [gunicorn](https://github.com/benoitc/gunicorn) from 20.1.0 to 23.0.0.
- [Release notes](https://github.com/benoitc/gunicorn/releases)
- [Commits](benoitc/gunicorn@20.1.0...23.0.0)

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

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

Author: dependabot[bot]

prod_requirements.txt

@@ -1,3 +1,3 @@
 -r requirements.txt
-gunicorn==20.1.0
+gunicorn==23.0.0
 raven==6.10.0