Add missing getSupportedTypes

Author: alexander-schranz

src/PHPCR/Shell/Serializer/NodeNormalizer.php

@@ -82,6 +82,13 @@ public function normalize($node, $format = null, array $context = []): ArrayObje
         return $res;
     }
 
+    public function getSupportedTypes(?string $format): array
+    {
+        return [
+            NodeInterface::class => true,
+        ];
+    }
+
     /**
      * {@inheritdoc}
      */