Previously, the WithTicker option would call TickScheduler.Tick every
time the underlying time.Ticker sent a time on its channel. This meant
we used a 1s period, which meant that in the worst case, we would see a
tick at about 999ms after the second rollover.
This change increases the underlying time.Ticker frequency, but only
calls TickScheduler.Tick after a second rolls over. Since we now use a
tick frequency of 100ms, during normal operation, TickScheduler.Tick
will be called within 0.1s after the second rolls over.
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