adding some type changes

src/shopifyApi.ts

@@ -890,6 +890,8 @@ export class ShopifyVariant {
   compareAtPrice?: number
   barcode?: string
   position?: number
+  metafields?: shopify.Metafield[]
+  inventory_item?: shopify.InventoryItemInput
   nodes?: ShopifyProductVariant[]
   //TODO: support multiple options
   optionValues: [{}] = [
@@ -1016,6 +1018,7 @@ export class ShopifyProductSetInput {
   title: string
   vendor: string
   variants: ShopifyVariant[]
+  metafields: shopify.MetafieldInput[]
   //TODO: Support multiple product options
   productOptions: [{}] = [
     {