cda9440a29 inadvertently fixes this in the
most frequent case by inverting the `TickDistanceMultiplier` from being
not-1 to 1 on beatmap versions above v8.
This can still potentially go wrong if a beatmap from a version below v8
is edited, because upon save it will be reencoded at the latest version,
meaning that the multiplier will change from not-1 to 1 - but this can
be handled separately.
Basically moves `PopoverContainer` to cover both the columns and the customisation panel, so that if the customisation panel is clicked on, the popover container will notice that and hide popovers like the mod preset popover.