See AF-18118.

To avoid skipping forward when we use omitStartLSN.

The underlying issue is that we didn't protect against the standby being significantly lagged and the oplog entries it was lagged having been truncated away on the standby read path. So we were reading those "phantom" collections since we didn't apply the oplog entries that had dropped them The fix would be to introduce a standby read path continuity check, failing which we crash to reload a new checkpoint upon restart. This checkpoint will have the result of the drops and so we won't encounter the phantom collections.