is-moving class doesn't get removed on spill

[WriterStat]

Replicate:

• Open jkanban Demo
• Move item, but leave in same place.
• Or move item and drop outside boards, so it spills.

class... is-moving gets set, but never gets removed. It stays on all spilled items. So there can be multiple is-moving identified items on multiple boards left not moving,

Doesn't seem good. If you are tracking is-moving items in any way.

Hope helps.