Add "id" field

schemas/2021-09-09/uiFormDefinition.schema.json

@@ -1,4 +1,5 @@
 {
+  "id": "https://schema.management.azure.com/schemas/2021-09-09/uiFormDefinition.schema.json#",
   "$schema": "http://json-schema.org/draft-07/schema",
   "definitions": {
     "createFormViewType": {
@@ -3930,4 +3931,4 @@
     }
   },
   "additionalProperties": false
-}
+}