Unlinks the given third-party user from your smart home Action. All data related to this user
will be deleted. For more details on how users link their accounts, see [fulfillment and
authentication](https://developers.google.com/assistant/smarthome/concepts/fulfillment-
authentication). The third-party user's identity is passed in via the `agent_user_id` (see
DeleteAgentUserRequest). This request must be authorized using service account credentials from
your Actions console project.
Create a request for the method "agentUsers.delete".
This request holds the parameters needed by the homegraph server. After setting any optional
parameters, call the
AbstractGoogleClientRequest.execute() method to invoke the remote operation.