In investigating coder/internal#109 I noticed many of the notification tests are still using `time.Sleep` and `require.Eventually`. This is an initial effort to start converting these to Quartz.

One product change is to switch the `notifier` to use a `TickerFunc` instead of a normal Ticker, since it allows the test to assert that a batch process is complete via the Quartz `Mock` clock.  This does introduce one slight behavioral change in that the notifier waits the fetch interval before processing its first batch.  In practice, this is inconsequential: no one will notice if we send notifications immediately on startup, or just a little later.

But, it does make a difference to some tests, which are fixed up here.

In investigating coder/internal#109 I noticed many of the notification tests are still using `time.Sleep` and `require.Eventually`. This is an initial effort to start converting these to Quartz.

One product change is to switch the `notifier` to use a `TickerFunc` instead of a normal Ticker, since it allows the test to assert that a batch process is complete via the Quartz `Mock` clock.  This does introduce one slight behavioral change in that the notifier waits the fetch interval before processing its first batch.  In practice, this is inconsequential: no one will notice if we send notifications immediately on startup, or just a little later.

But, it does make a difference to some tests, which are fixed up here.