MachineLearningNotebooks: Re-registering a dataset does not create new version

When trying to register a dataset with the flag create_new_version=True, I get an error instead of creating a new version.

I get the following error:

  File "register.py", line 110, in register_dataset
    ds.register(workspace, name=name, create_new_version=True)
  File "/data/anaconda/envs/cyril/lib/python3.6/site-packages/azureml/data/_loggerfactory.py", line 106, in wrapper
    return func(*args, **kwargs)
  File "/data/anaconda/envs/cyril/lib/python3.6/site-packages/azureml/data/abstract_dataset.py", line 313, in register
    raise result
Exception: An identical dataset had already been registered, which can be retrieved with `Dataset.get_by_name(workspace, name="cases_train_data.csv", version=1)`.

Here is my call to register the data set:

    ds = Dataset.Tabular.from_delimited_files(path)
    ds.register(workspace, name=name, create_new_version=True)

SDK Version: azureml-sdk==1.2.0