Correct routing test spelling mistake.

actionpack/test/controller/routing_test.rb

@@ -213,7 +213,7 @@ def test_optional_star_paths_are_greedy_but_not_too_much
     assert_equal expected, ActiveSupport::JSON.decode(get(u))
   end
 
-  def test_regexp_precidence
+  def test_regexp_precedence
     rs.draw do
       get "/whois/:domain", constraints: {
         domain: /\w+\.[\w\.]+/ },