Remove final from ItemNormalizer (add a PHPDoc final instead)

Author: alanpoulain

src/Serializer/ItemNormalizer.php

@@ -18,9 +18,11 @@
 /**
  * Generic item normalizer.
  *
+ * @final
+ *
  * @author Kévin Dunglas <[email protected]>
  */
-final class ItemNormalizer extends AbstractItemNormalizer
+class ItemNormalizer extends AbstractItemNormalizer
 {
     /**
      * {@inheritdoc}