Update README.md

Author: abuzuhri

README.md

@@ -27,6 +27,7 @@ The purpose of this package is to have an easy way of getting started with the A
 - [x] [Reports](https://github.com/amzn/selling-partner-api-docs/blob/main/references/reports-api/reports_2020-09-04.md)
 - [x] [FinancesV0](https://github.com/amzn/selling-partner-api-docs/blob/main/references/finances-api/financesV0.md)
 - [x] [Feeds](https://github.com/amzn/selling-partner-api-docs/blob/main/references/feeds-api/feeds_2021-06-30.md) for [feedType](https://github.com/amzn/selling-partner-api-docs/blob/main/references/feeds-api/feedtype-values.md) for step to call feed read [doc](https://github.com/amzn/selling-partner-api-docs/blob/main/guides/en-US/use-case-guides/feeds-api-use-case-guide/feeds-api-use-case-guide_2021-06-30.md)
+- [ ] [ListingsItems](https://github.com/amzn/selling-partner-api-docs/blob/main/references/listings-items-api/listingsItems_2021-08-01.md)
 - [x] [Uploads](https://github.com/amzn/selling-partner-api-docs/blob/main/references/uploads-api/uploads_2020-11-01.md)
 - [x] [shipmentInvoicingV0](https://github.com/amzn/selling-partner-api-docs/blob/main/references/shipment-invoicing-api/shipmentInvoicingV0.md)
 - [x] [Shippings](https://github.com/amzn/selling-partner-api-docs/blob/main/references/shipping-api/shipping.md)