style: Fix PHP-CS-Fixer docblock formatting

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: jarstelfox

tests/Serializer/AbstractSerializerTest.php

@@ -80,6 +80,7 @@ public function testBackedEnumsIncludeValue(): void
 
     /**
      * @requires PHP >= 8.1
+     *
      * @dataProvider serializeAllObjectsDataProvider
      */
     public function testEnumsAreNotSerializedAsObjects(bool $serializeAllObjects): void
@@ -98,6 +99,7 @@ public function testEnumsAreNotSerializedAsObjects(bool $serializeAllObjects): v
 
     /**
      * @requires PHP >= 8.1
+     *
      * @dataProvider serializeAllObjectsDataProvider
      */
     public function testBackedEnumsAreNotSerializedAsObjects(bool $serializeAllObjects): void