A streaming replica waiting on WAL from the master will wake up every 5 seconds to check for a trigger file. This is pointless if no trigger file has been configured.
The attached patch suppresses the timeout when there is no trigger file configured.
A minor thing to be sure, but there was a campaign a couple years ago to remove such spurious wake-ups, so maybe this change is worthwhile.
I noticed that the existing codebase does not have a consensus on what to pass to WaitLatch for the timeout when the timeout isn't relevant. I picked 0, but -1L also has precedent.
