add product recommendation for automl tables notebook

[TheMichaelHu]

Add a notebook demonstrating how recommendations can be made using automl tables.

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[TheMichaelHu]

@beccasaurus / @sirtorry qq about code reviews for this repo: my team is curious to know if the expectation is that we do a code review ourselves for readability/functionality that meets google code standards prior to submitting here or if reviewers for this repo do a sufficiently in-depth review that we shouldn't need to ourselves.

[beccasaurus]

@TheMichaelHu Good question! Tbh we haven't formalized process around Notebooks (versus small snippets and small sample applications, which is mostly what resides in this repository).

@gogasca Do you have any thoughts on this?

For non-Notebook code, we have process and tooling + we require system tests to verify functionality. We don't have any of that for Notebooks at the moment.

[gogasca]

@TheMichaelHu Good question! Tbh we haven't formalized process around Notebooks (versus small snippets and small sample applications, which is mostly what resides in this repository).

@gogasca Do you have any thoughts on this?

For non-Notebook code, we have process and tooling + we require system tests to verify functionality. We don't have any of that for Notebooks at the moment.

1. In regards testing notebooks, we have the code/solution required to test Notebooks via CI/CD, just need to implement it in the repo (will check if I have some cycles next month).
   https://github.com/GoogleCloudPlatform/ai-platform-samples/tree/master/notebooks/notebooks-ci-showcase
2. As far as best practices I see Michael is internal will send him the templates and documentation.

[sirtorry]

let's hold off until googleapis/google-cloud-python#8720

[TheMichaelHu]

Looks like googleapis/google-cloud-python#8720 went through, I'll rewrite using the new API after the next version is out

[sirtorry]

need to implement ci/cd for testing at a later date.