minor #7398 Add missing use statement (Totof6942)

This PR was merged into the 2.7 branch.

Discussion
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Add missing use statement

Commits
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de7a260 Add missing use statement

Author: xabbuh

routing/redirect_trailing_slash.rst

@@ -42,6 +42,7 @@ system, as explained below:
         // src/AppBundle/Controller/RedirectingController.php
         namespace AppBundle\Controller;
 
+        use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route;
         use Symfony\Bundle\FrameworkBundle\Controller\Controller;
         use Symfony\Component\HttpFoundation\Request;