Set the resource id on ProductVariantMetafield when creating

Author: jswift

src/BigCommerce/Api/Catalog/Products/ProductVariant/ProductVariantMetafieldsApi.php

@@ -71,6 +71,7 @@ public function getAll(array $filters = [], int $page = 1, int $limit = 250): Pr
 
     public function create(ProductVariantMetafield $metafield): ProductVariantMetafieldResponse
     {
+        $metafield->resource_id = $this->getParentResourceId() ?? 0;
         return new ProductVariantMetafieldResponse($this->createResource($metafield));
     }