Minor CS fixes

Author: nicolas-grekas

Tests/Extension/Validator/ViolationMapper/ViolationMapperTest.php

@@ -13,7 +13,6 @@
 
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\EventDispatcher\EventDispatcher;
-use Symfony\Component\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\Form\CallbackTransformer;
 use Symfony\Component\Form\Exception\TransformationFailedException;
 use Symfony\Component\Form\Extension\Core\DataMapper\DataMapper;

Tests/FormFactoryTest.php

@@ -16,7 +16,6 @@
 use Symfony\Component\Form\Extension\Core\Type\TextType;
 use Symfony\Component\Form\FormFactory;
 use Symfony\Component\Form\FormRegistry;
-use Symfony\Component\Form\FormRegistryInterface;
 use Symfony\Component\Form\FormTypeGuesserChain;
 use Symfony\Component\Form\FormTypeGuesserInterface;
 use Symfony\Component\Form\Guess\Guess;