Removed excluding vendor from API doc [ci skip]

These folder not exists in system

railties/lib/rails/api/task.rb

@@ -16,8 +16,7 @@ class Task < RDoc::Task
           :include => %w(
             README.rdoc
             lib/active_record/**/*.rb
-          ),
-          :exclude => 'lib/active_record/vendor/*'
+          )
         },
 
         'activemodel' => {
@@ -33,8 +32,7 @@ class Task < RDoc::Task
             lib/abstract_controller/**/*.rb
             lib/action_controller/**/*.rb
             lib/action_dispatch/**/*.rb
-          ),
-          :exclude => 'lib/action_controller/vendor/*'
+          )
         },
 
         'actionview' => {
@@ -49,8 +47,7 @@ class Task < RDoc::Task
           :include => %w(
             README.rdoc
             lib/action_mailer/**/*.rb
-          ),
-          :exclude => 'lib/action_mailer/vendor/*'
+          )
         },
 
         'railties' => {