minor #20833 [Routing] Adds missing use statement (silasjoisten)

This PR was submitted for the 7.2 branch but it was merged into the 6.4 branch instead.

Discussion
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[Routing] Adds missing use statement

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Commits
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dae33e4 Adds missing use statement

Author: OskarStark

Diff for: routing.rst

@@ -969,6 +969,7 @@ optional ``priority`` parameter in those routes to control their priority:
         namespace App\Controller;
 
         use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
+        use Symfony\Component\HttpFoundation\Response;
         use Symfony\Component\Routing\Attribute\Route;
 
         class BlogController extends AbstractController