Changes to List webhooks

the items/webhook/id response's property type changed from no type to string for status 200

added the new disk_snapshot_restored enum value to the items/webhook/eventFilter/items response property for the response status 200

added the optional property code to the response with the 400 status

added the optional property code to the response with the 401 status

added the optional property code to the response with the 404 status

added the optional property code to the response with the 429 status

added the optional property code to the response with the 500 status

added the optional property code to the response with the 503 status

the items/webhook/id response's property pattern ^whk-[0-9a-z]{20}$ was added for the status 200