LYNX-369: add element for mftf test (#223)

Author: eliseacornejo

app/code/Magento/Sales/Test/Mftf/Section/AdminOrderFormItemsSection.xml

@@ -37,6 +37,7 @@
         <element name="applyCoupon" type="button" selector="#order-coupons button"/>
         <element name="removeCoupon" type="button" selector=".added-coupon-code .action-remove"/>
         <element name="removeSpecificCoupon" type="button" selector=".added-coupon-code.coupon-code-{{couponCode}} .action-remove" parameterized="true"/>
+        <element name="couponCodeApplied" type="text" selector=".added-coupon-code.coupon-code-{{couponCode}} span" parameterized="true"/>
         <element name="totalRecords" type="text" selector="#sales_order_create_search_grid-total-count"/>
         <element name="numberOfPages" type="text" selector="div.admin__data-grid-pager-wrap div.admin__data-grid-pager > label"/>
         <element name="productName" type="button" selector="(.//*[@class='col-product'])[2]/span"/>