Adding the route_key and param_key tests

This way all the tests are testing the same fields

activemodel/test/cases/naming_test.rb

@@ -29,6 +29,14 @@ class NamingTest < ActiveModel::TestCase
     assert_equal 'Track back', @model_name.human
   end
 
+  def test_route_key
+    assert_equal 'post_track_backs', @model_name.route_key
+  end
+
+  def test_param_key
+    assert_equal 'post_track_back', @model_name.param_key
+  end
+
   def test_i18n_key
     assert_equal :"post/track_back", @model_name.i18n_key
   end