vmwarecloudsimple: adding a missing type to the datetime field (Azure#16090)

Author: tombuildsstuff

specification/vmwarecloudsimple/resource-manager/Microsoft.VMwareCloudSimple/stable/2019-04-01/vmwarecloudsimple.json

@@ -2557,7 +2557,8 @@
         "created": {
           "description": "date time the resource was created",
           "format": "date-time",
-          "readOnly": true
+          "readOnly": true,
+          "type": "string"
         },
         "nodesCount": {
           "description": "count of nodes to create",