event.operation.target is null on onDragStart Event

Hello everyone,

I recently updated to v0.4.0 and noticed a change at the onDragStart event.
Before 0.4.0 I used event.operation.target on onDragStart to determine from which Droppable a Draggable was initially dragged out.

With v0.4.0 event.operation.target on onDragStart is always null.

I went back to v0.3.2 and it worked like before.

But I don't know if it is a bug or if I did use that event property in uninteded ways previously.

Reproduce the onDragStart behavior in dnd-kit v0.4.0 and compare event.operation.target with v0.3.2, where the reporter observed a non-null value. First determine whether the change is intentional and what target behavior is expected; done means the behavior is clarified and, if it is a regression, covered by an appropriate test.

Written by the indexing model from the issue text.