Long tests

I was looking at a recent test run and saw this

```python
1000.12s call tests/model_selection/test_incremental.py::test_basic
17.06s call tests/model_selection/dask_searchcv/test_model_selection.py::test_as_completed_distributed
10.88s call tests/test_kmeans.py::test_check_estimator
8.63s call tests/model_selection/test_split.py::test_20_newsgroups
8.35s call tests/model_selection/test_incremental.py::test_search_basic
6.90s call tests/model_selection/dask_searchcv/test_model_selection.py::test_scheduler_param[multiprocessing-4]
6.30s call tests/model_selection/test_incremental.py::test_warns_scores_per_fit
5.72s call tests/test_incremental.py::test_score
5.48s call tests/model_selection/test_incremental.py::test_small
4.98s call tests/model_selection/dask_searchcv/test_model_selection.py::test_scheduler_param_distributed
```

It looks like we have a `timeout=1000` in one of our tests.

Running this locally test_basic does seem to hang for me for quite a while