fix Psalm covariantT misparse on ClassMetadata with doctrine/persistence 3.4

Bind the generic template T to object via @param ClassMetadata<object> so
Psalm no longer tries to resolve the unbound @template-covariant T as a
class named Doctrine\Persistence\Mapping\covariantT.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: dpfaffenbauer

src/CoreShop/Bundle/ResourceBundle/EventListener/AbstractDoctrineSubscriber.php

@@ -34,6 +34,9 @@ public function __construct(
     ) {
     }
 
+    /**
+     * @param ClassMetadata<object> $metadata
+     */
     protected function isResource(ClassMetadata $metadata): bool
     {
         return $metadata->getReflectionClass()->implementsInterface(ResourceInterface::class);