Always delete the AREASxxxxxx temp file

When there are no changes (areas added or removed) via an areafix message, the
data/AREASxxxxxx temp file would be left behind. The file was only removed if
areas were added or removed from the area file via areafix message.

The orphaned data/AREASxxxxxxx files were reported via DOVE-Net by Gamgee (PALANTIR)
If you have these stale files, you can safely delete them.