CopyAttributesHandler copies attributes from a newer position onto an older, late-arriving one

If a position arrives late (buffered/retransmitted, or a batch upload where older fixes are sent after newer ones), the cached "last" position can be newer than the one currently being processed. Copying attributes from a more recent position onto an older one doesn't make sense. It's pretty common to copy driverUniqueId, and in this case it can be a big problem — a late position gets attributed to whichever driver was assigned at the time of the newer position, not the driver who was actually driving when the late position was recorded.

Suggested fix: only copy when last is not newer than the position being processed, happy to open a PR against master with it if that's welcome.