Docs: Match example with the sentance. [ci-skip]

Match the code example with the description.

Co-authored-by: Louis-Michel Couture <louim_1@hotmail.com>

actionpack/lib/action_dispatch/http/parameters.rb

@@ -78,7 +78,7 @@ module ActionDispatch
       # Returns a hash with the \parameters used to form the \path of the request.
       # Returned hash keys are symbols:
       #
-      #   {'action' => 'my_action', 'controller' => 'my_controller'}
+      #   { action: "my_action", controller: "my_controller" }
       def path_parameters
         get_header(PARAMETERS_KEY) || set_header(PARAMETERS_KEY, {})
       end