Adding a notebook for the feature store spark ingestion

[philikai]

Issue #, if available:

Description of changes: All changes in section 5!

• Added a notebook "05-04...." to perform batch ingestion with spark (derived from notebook 05-02)
• Added Feature store manager scripts for easy use
• updated Readme of section 5
• updated notebook 05-02 with description of difference to 05-04

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[ioanfr]

Files reviewed and tested