This can happen if the online IDs are not present in the `.osu` files.
Previously this was only working due to the early logic in the import
process (that relies on matching all online IDs perfectly).
Carousel would only expire items when off-screen. This meant that for a
case (like a test) where items are generally always on-screen,
`UpdateBeatmapSet` calls would result in panels remaining hidden but not
cleaned up.