Merge pull request #569 from 3scale/upgrade-rack-2.16

Upgrade rack to 2.2.20 for 2.16

Author: mayorova

Gemfile.lock

@@ -241,7 +241,7 @@ GEM
       que (>= 1)
       sinatra
     racc (1.8.1)
-    rack (2.2.12)
+    rack (2.2.20)
     rack-protection (2.2.3)
       rack
     rack-test (2.1.0)