Fix BC break with DoctrineType::reset() for Symfony 3.4-4.1

Fixes BC break with mistakenly removed `kernel.reset` tag from
`form.type.entity` service, because `DoctrineType` implements
`ResetInterface` only in Symfony 4.2+, therefore all previous
versions starting from 3.4 are affected.

This BC break was introduced in version 1.11.0 in commit 6b25ea4

DependencyInjection/DoctrineExtension.php

@@ -11,6 +11,7 @@
 use Doctrine\ORM\Version;
 use LogicException;
 use Symfony\Bridge\Doctrine\DependencyInjection\AbstractDoctrineExtension;
+use Symfony\Bridge\Doctrine\Form\Type\DoctrineType;
 use Symfony\Bridge\Doctrine\Messenger\DoctrineTransactionMiddleware;
 use Symfony\Bridge\Doctrine\PropertyInfo\DoctrineExtractor;
 use Symfony\Bridge\Doctrine\Validator\DoctrineLoader;
@@ -343,6 +344,11 @@ protected function ormLoad(array $config, ContainerBuilder $container)
         $loader = new XmlFileLoader($container, new FileLocator(__DIR__ . '/../Resources/config'));
         $loader->load('orm.xml');
 
+        // This check can be removed when support for Symfony < 4.2 is dropped
+        if (method_exists(DoctrineType::class, 'reset')) {
+            $container->getDefinition('form.type.entity')->addTag('kernel.reset', ['method' => 'reset']);
+        }
+
         $entityManagers = [];
         foreach (array_keys($config['entity_managers']) as $name) {
             $entityManagers[$name] = sprintf('doctrine.orm.%s_entity_manager', $name);