Check tests that are commented out

[dengdifan]

Some tests, e.g., tests/test_model/test_gp.py::test_gp_on_sklearn_data tests/test_model/test_gp_mcmc.py::test_predict_with_actual_values tests/test_model/test_gp_mcmc.py::test_gp_on_sklearn_data tests/test_model/test_rf.py::test_rf_on_sklearn_data

We need to check that if they still work and replace the load_boston with load_diabetes