SERVER-106463 added a retry loop (assertSetFCVSoon) to the teardown of various FSM tests to guard against leftover setFCV invocations from the FSM conflicting with it.

This isn't necessary because setFCV doesn't fork background work, so in the teardown no setFCV commands from the FSM states should be running. Furthermore setFCV invocations serialize via the setFCVCommandLock. In addition some of the errors that are retried indicate definitive failures for which retrying won't help.

Remove (or at least reduce) the retry loop as it may mask setFCV failures we should investigate.