Add unit tests
-
test_fetch_series_by_code -
test_fetch_series_by_code_mask -
test_fetch_series_by_code_mask_with_plus_in_dimension_code -
test_fetch_series_by_id -
test_fetch_series_by_ids_in_same_dataset -
test_fetch_series_by_ids_in_different_datasets -
test_fetch_series_by_dimension -
test_fetch_series_of_dataset -
test_fetch_series_by_api_link -
test_fetch_series_with_na_values -
test_fetch_series_with_max_nb_series -
test_fetch_series_with_filter_on_one_series -
test_fetch_series_with_filter_on_one_series_with_filter_error
(Source: test suite of the Python client (https://git.nomics.world/dbnomics/dbnomics-python-client/blob/master/tests/test_client.py))