Adding xms-ids for Commerce (#17628)

Author: agalerrotaru

specification/commerce/resource-manager/Microsoft.Commerce/preview/2015-06-01-preview/commerce.json

@@ -301,13 +301,19 @@
           "items": {
             "$ref": "#/definitions/OfferTermInfo"
           },
+          "x-ms-identifiers": [
+            "Name"
+          ],
           "description": "A list of offer terms."
         },
         "Meters": {
           "type": "array",
           "items": {
             "$ref": "#/definitions/MeterInfo"
           },
+          "x-ms-identifiers": [
+            "MeterId"
+          ],
           "description": "A list of meters."
         }
       }