trigger_next_expired_timer_at (SystemTimer::ConcurrentTimerPool)

        # File lib/system_timer/concurrent_timer_pool.rb, line 52
    52:     def trigger_next_expired_timer_at(now_in_seconds_since_epoch)
    53:       timer = next_expired_timer(now_in_seconds_since_epoch)
    54:       return if timer.nil?
    55:
    56:       cancel timer
    57:       log_timeout_received(timer) if SystemTimer.debug_enabled?
    58:       timer.thread.raise Timeout::Error.new("time's up!")
    59:     end