Bump gunicorn from 20.0.4 to 22.0.0

Bumps [gunicorn](https://github.com/benoitc/gunicorn) from 20.0.4 to 22.0.0.
- [Release notes](https://github.com/benoitc/gunicorn/releases)
- [Commits](benoitc/gunicorn@20.0.4...22.0.0)

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

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

setup.py

@@ -27,7 +27,7 @@
     "flask-swagger==0.2.14",
     "flask-swagger-ui==3.25.0",
     "Jinja2>=2.10.1,<3.1",
-    "gunicorn==20.0.4",
+    "gunicorn==22.0.0",
     "coloredlogs==15.0.1",
     "Werkzeug==2.0.3",
     "eciespy==0.3.11",