gcp/appengine: update gunicorn to 22.0.0 (#2116)

This should resolve
https://github.com/google/osv.dev/security/dependabot/170

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Co-authored-by: Andrew Pollock <[email protected]>

Author: 2 people

gcp/appengine/Pipfile

@@ -20,7 +20,7 @@ packaging = "==21.3"
 redis = "==4.6.0"
 requests = "==2.31.0"
 grpcio-status = "==1.62.0"
-gunicorn = "==21.2.0"
+gunicorn = "==22.0.0"
 whitenoise = "6.5.0"
 
 [dev-packages]