[bug] Sortable swapping does not work when forceFallback is enabled and a handle or content is a custom element (web component) with a shadowRoot #2346

Describe the bug

• When in forceFallback: true, and the handle or list content is a web component with an open shadowRoot items cannot be dragged.
• In our usage, our handle element is another custom element with shadowRoot and the content within a sortable element is also a custom element.
• The code problem area is seen in this section:

  Sortable/src/Sortable.js

  Lines 756 to 759 in 07708fa

  	while (target && target.shadowRoot) {
  	target = target.shadowRoot.elementFromPoint(touchEvt.clientX, touchEvt.clientY);
  	if (target === parent) break;
  	parent = target;

• With this line target = target.shadowRoot.elementFromPoint(touchEvt.clientX, touchEvt.clientY);, its returning elements within our handle custom element or content custom element instead of a child of the Sortable instance.
• This only happens when in forceFallback: true or when used by a mobile device which seems to always go into fallback mode.
• When using native drag and drop the issue is not seen.

To Reproduce
Steps to reproduce the behavior:

1. Go to https://codepen.io/driskull/pen/OJqrzVL?editors=1010
2. Try to drag a handle over another handle and notice it won't swap elements
3. Drag a handle over a list element textContent and notice it does swap
4. If there are other custom-elements inside the list-element in place of the text content elements won't swap either.
5. See sample: https://codepen.io/driskull/pen/xxBmpra?editors=0110

Expected behavior

I would expect sort swapping to work when a handle or content within a list is a custom element.

Information

sortablejs = ^1.15.1
@types/sortablejs = ^1.15.1

Additional context
I have a PR open to fix this but need verification that it is the best approach to fixing the issue.

Reproduction
codesandbox: https://codepen.io/driskull/pen/OJqrzVL?editors=1010 and https://codepen.io/driskull/pen/xxBmpra?editors=0110

Pull Request Fix

#2347