minor #12995 Updated imports in TaskController when using TaskType (phpfour)

This PR was submitted for the 4.4 branch but it was merged into the 4.3 branch instead (closes #12995).

Discussion
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Updated imports in TaskController when using TaskType

Removed unused imports and added a required import.

Commits
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2e6ac11 Updated imports in TaskController when using TaskType

Author: javiereguiluz

forms.rst

@@ -262,10 +262,8 @@ to build another object with the visual representation of the form::
     namespace App\Controller;
 
     use App\Entity\Task;
+    use App\Form\Type\TaskType;
     use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
-    use Symfony\Component\Form\Extension\Core\Type\DateType;
-    use Symfony\Component\Form\Extension\Core\Type\SubmitType;
-    use Symfony\Component\Form\Extension\Core\Type\TextType;
     use Symfony\Component\HttpFoundation\Request;
 
     class TaskController extends AbstractController