Replace deprecated getObject with getObjectNode

CloudObjects/SDK/JSON/SchemaValidator.php

@@ -68,7 +68,7 @@ class SchemaValidator {
      * @param Node $node The COID of the specification.
      */
     public function validateAgainstCOID($data, IRI $coid) {
-        $object = $this->objectRetriever->getObject($coid);
+        $object = $this->objectRetriever->getObjectNode($coid);
         Assert::true($this->reader->hasType($object, 'json:Element'),
             "You can only validate data against JSON elements!");
         $this->validateAgainstNode($data, $object);