minor #20973 [Doctrine] Remove redundant example with attribute (HypeMC)

This PR was merged into the 6.4 branch.

Discussion
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[Doctrine] Remove redundant example with attribute

The attribute block is redundant, as this section covers alternatives to an attribute already demonstrated in the previous section.

Commits
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62b7149 [Doctrine] Remove redundant example with attribute

Author: xabbuh

doctrine/events.rst

@@ -304,23 +304,6 @@ listener in the Symfony application by creating a new service for it and
 
 .. configuration-block::
 
-    .. code-block:: php-attributes
-
-        // src/EventListener/SearchIndexer.php
-        namespace App\EventListener;
-
-        use Doctrine\Bundle\DoctrineBundle\Attribute\AsDoctrineListener;
-        use Doctrine\ORM\Event\PostPersistEventArgs;
-
-        #[AsDoctrineListener('postPersist'/*, 500, 'default'*/)]
-        class SearchIndexer
-        {
-            public function postPersist(PostPersistEventArgs $event): void
-            {
-                // ...
-            }
-        }
-
     .. code-block:: yaml
 
         # config/services.yaml