Fixed broken external link to DemoController Test

Author: danielsan

book/testing.rst

@@ -852,6 +852,6 @@ Learn more
 * :doc:`/cookbook/testing/profiling`
 * :doc:`/cookbook/testing/bootstrap`
 
-.. _`DemoControllerTest`: https://github.com/symfony/symfony-standard/blob/master/src/Acme/DemoBundle/Tests/Controller/DemoControllerTest.php
+.. _`DemoControllerTest`: https://github.com/sensiolabs/SensioDistributionBundle/blob/master/Resources/skeleton/acme-demo-bundle/Acme/DemoBundle/Tests/Controller/DemoControllerTest.php
 .. _`$_SERVER`: http://php.net/manual/en/reserved.variables.server.php
 .. _`documentation`: http://phpunit.de/manual/current/en/