linear_learner_mnist_with_file_system_data_source.ipynb failed CI

Link to the notebook:
https://github.com/aws/amazon-sagemaker-examples/blob/master/introduction_to_amazon_algorithms/linear_learner_mnist/linear_learner_mnist_with_file_system_data_source.ipynb

Error:

---------------------------------------------------------------------------
Exception encountered at "In [2]":
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
in
21 file_system_type=file_system_type,
22 directory_path=file_system_directory_path,
---> 23 file_system_access_mode=file_system_access_mode)

/opt/conda/lib/python3.7/site-packages/sagemaker/inputs.py in __init__(self, file_system_id, file_system_type, directory_path, file_system_access_mode, content_type)
143 raise ValueError(
144 "Unrecognized file system type: %s. Valid values: %s."
--> 145 % (file_system_type, ", ".join(FILE_SYSTEM_

[...]

ValueError: Unrecognized file system type: . Valid values: FSxLustre, EFS.

Start with introduction_to_amazon_algorithms/linear_learner_mnist/linear_learner_mnist_with_file_system_data_source.ipynb and inspect cell In[2], where the ValueError occurs. Run the notebook or its CI check and determine what change is needed so the file-system data source uses a recognized configuration and the notebook completes without this error.

Written by the indexing model from the issue text.