ReadonlybuildReturns the heartbeat to send now (for example from buildHeartbeat), or undefined
to skip this interval.
Optional ReadonlyclockThe time source of the waits (default systemClock).
Optional ReadonlyloggerThe logger (default defaultLogger).
ReadonlysendSends it: restHeartbeatSend or a gateway callback.
Optional ReadonlysettingsSettings; pollIntervalMs (sdk.poll_interval) is the wait before the first answer.
The options of HeartbeatSender.