minor #14307 Update user_provider.rst (Yoann-TYT)

This PR was merged into the 4.4 branch.

Discussion
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Update user_provider.rst

ServiceEntityRepository instead of EntityRepository ( Using a Custom Query to Load the User )

Commits
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fbf5348 Update user_provider.rst

Author: OskarStark

security/user_provider.rst

@@ -128,23 +128,24 @@ interface only requires one method: ``loadUserByUsername($username)``::
     // src/Repository/UserRepository.php
     namespace App\Repository;
 
-    use Doctrine\ORM\EntityRepository;
+    use Doctrine\Bundle\DoctrineBundle\Repository\ServiceEntityRepository;
     use Symfony\Bridge\Doctrine\Security\User\UserLoaderInterface;
 
-    class UserRepository extends EntityRepository implements UserLoaderInterface
+    class UserRepository extends ServiceEntityRepository implements UserLoaderInterface
     {
         // ...
 
         public function loadUserByUsername($usernameOrEmail)
         {
-            return $this->createQuery(
+            $entityManager = $this->getEntityManager();
+            
+            return $entityManager->createQuery(
                     'SELECT u
                     FROM App\Entity\User u
                     WHERE u.username = :query
                     OR u.email = :query'
                 )
                 ->setParameter('query', $usernameOrEmail)
-                ->getQuery()
                 ->getOneOrNullResult();
         }
     }