MQE-1227: "Required" attribute value is skipped for metadata

Author: jilu1

src/Magento/FunctionalTestingFramework/DataGenerator/Objects/OperationElement.php

@@ -64,7 +64,7 @@ public function __construct($key, $value, $type, $required, $nestedElements = []
         $this->value = $value;
         $this->type = $type;
         $this->nestedElements = $nestedElements;
-        if ($required) {
+        if (filter_var($required, FILTER_VALIDATE_BOOLEAN)) {
             $this->required = true;
         } else {
             $this->required = false;