public synchronized ScheduledFuture<?> scheduleTask(
      final Runnable command, final long delay, final TimeUnit unit) {
    assertRunning();
    return timerExecutor.schedule(command, delay, unit);
  }
Schedule task.

@param command the command
@param delay the delay
@param unit the unit
@return the scheduled future
consensus/common/src/main/java/org/hyperledger/besu/consensus/common/bft/BftExecutors.java