Dragging/reordering of list items in work items is broken
## Problem
Dragging/reordering of list items in work items appears to be broken. When attempting to drag an item:
- The drag can be initiated
- The item never moves to the new position
- The drag cannot be cancelled without reloading the page
{width=900 height=579}
## Environment
- Tested in Firefox and Chrome
- Reported by @markrian
## More Context
It worked at least 6 months ago, when Mark worked on https://gitlab.com/gitlab-org/gitlab/-/merge_requests/181665+
## Proposal
- fix the bug, plus [this MR](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/181665) is merged
- remove the feature (related question: https://gitlab.com/gitlab-org/gitlab/-/work_items/595151#note_3201888197)
## Related
- [Initial report](https://gitlab.slack.com/archives/CETG54GQ0/p1774373985333959)
- https://gitlab.com/gitlab-org/gitlab/-/merge_requests/181665+
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