Fix rects measuring on elements change

[akantic]

A fix for #1092, I am not sure if there are any other implications with this change so any input is appreciated.

What was happening?

When using multiple containers scrollableAncestors would get updated, but their rects would not.
So, let's imagine dragging from one container to another, first we have something like:

scrollableAncestors = [parent, grandparent]
scrollableAncestorsRects = [parentRect, grandparentRect]

Then ancestors get updated to just one element in between switching containers, but rects do not.

scrollableAncestors = [grandparent]
scrollableAncestorsRects = [parentRect, grandparentRect]

Then, this code brings chaos:

dnd-kit/packages/core/src/hooks/utilities/useAutoScroller.ts

Lines 121 to 122 in 5c58f0f

	const index = scrollableAncestors.indexOf(scrollContainer);
	const scrollContainerRect = scrollableAncestorRects[index];

Because for grandparent scrollContainer it would use index 0 to access rects, leading to scrollContainerRect being parentRect for grandparent container - causing seemingly random jumps as can be seen in the video from the issue referenced on top.

[changeset-bot]

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Latest commit: 3c20737

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