Merge pull request #22475 from claudiob/missing-require

Add missing require to strong_parameters.rb

actionpack/lib/action_controller/metal/strong_parameters.rb

@@ -3,6 +3,7 @@
 require 'active_support/core_ext/string/filters'
 require 'active_support/rescuable'
 require 'action_dispatch/http/upload'
+require 'rack/test'
 require 'stringio'
 require 'set'