Vertex AI Integration lacks significant production quality issues

[DougEbel]

Last activity was by Doug when doing renaming of notebooks and directories. No record of who created it.

• Demo has no query band
• Doesn't appear to use demo_user
• DATABASE_URL='teradatasql://dbc:dbc@34.121.78.209/mldb'
• must have been missed for pass5 since it doesn't follow brand standards

I categorize de-publishing this demo as High because users won't be successful. It can be reprioritized/reassigned later if judged to be worth curating.

[DallasBowden]

We've decided to remove this notebook.