Whenever we update the lastDurable timestamp, we do two things:

1) Update `lastCommitted` and `commit point` if WriteConcernMajorityShouldJournal == true, which would eventually call `_wakeReadyWaiters()` if the committed point is advanced.

2) Right after the above step, call `_wakeReadyWaiters` again.

This seems to be duplicate work as they are called under the same mutex, we could consider skip calling `_wakeReadyWaiters` in step 1) and only walk through all the waiters in step 2).

Note this is based on code inspection, we should double check this before doing the changes.