Regression in `test_decide_worker_coschedule_order_neighbors`

https://github.com/dask/dask/pull/10535 broke `test_decide_worker_coschedule_order_neighbors`:

https://github.com/dask/distributed/actions/runs/6469648247/job/17564120071?pr=8253
```
            # No more than 2 workers should have any keys
>           assert sum(any(k in w.data for k in keys) for w in workers) <= 2
E           assert 5 <= 2
```

