Refacto development automl common backend debug (#2)

* [ADD] debug information

* [FIX] try fork for more stability

test/test_ensemble/test_ensemble.py

@@ -718,10 +718,10 @@ def test_ensemble_builder_nbest_remembered(fit_ensemble, ensemble_backend, dask_
         max_iterations=None,
     )
 
-    manager.build_ensemble(dask_client, unit_test=True)
+    manager.build_ensemble(dask_client, unit_test=True, pynisher_context='fork')
     future = manager.futures[0]
     dask.distributed.wait([future])  # wait for the ensemble process to finish
-    assert future.result() == ([], 5, None, None)
+    assert future.result() == ([], 5, None, None), vars(future.result())
     file_path = os.path.join(ensemble_backend.internals_directory, 'ensemble_read_preds.pkl')
     assert not os.path.exists(file_path)