minor #15769 [DependencyInjection] add missing use statements (dunglas)

This PR was merged into the 4.4 branch.

Discussion
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[DependencyInjection] add missing use statements

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Commits
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c381307 [DependencyInjection] add missing use statements

Author: javiereguiluz

service_container.rst

@@ -33,6 +33,7 @@ service's class or interface name. Want to :doc:`log </logging>` something? No p
 
     use Psr\Log\LoggerInterface;
     use Symfony\Component\HttpFoundation\Response;
+    use Symfony\Component\Routing\Annotation\Route;
 
     class ProductController
     {
@@ -122,6 +123,7 @@ inside your controller::
     // src/Controller/ProductController.php
     use App\Service\MessageGenerator;
     use Symfony\Component\HttpFoundation\Response;
+    use Symfony\Component\Routing\Annotation\Route;
 
     /**
      * @Route("/products/new")