docs: add empty lines in sample code

Author: kenjis

user_guide_src/source/incoming/incomingrequest/022.php

@@ -7,7 +7,9 @@ final class MyMenuTest extends CIUnitTestCase
     public function testActiveLinkUsesCurrentUrl()
     {
         service('request')->setPath('users/list');
+
         $menu = new MyMenu();
+
         $this->assertTrue('users/list', $menu->getActiveLink());
     }
 }