Feat: Extract the tabular metadata for Cloud Datasets program

[happyhuman]

Description

Note: If you are adding or editing a dataset, please specify the dataset folder involved, e.g. datasets/google_trends

Checklist

• [x] (Required) This pull request is appropriately labeled
• [x] Please merge this pull request after it's approved

Use the sections below based on what's applicable to your PR and delete the rest:

Feature

• [ ] I'm adding or editing a feature
• [ ] I have updated the README accordingly
• [ ] I have added/revised tests for the feature

Data Onboarding

• [x] I'm adding or editing a dataset
• [x] The Google Cloud Datasets team is aware of the proposed dataset
• [x] I put all my code inside datasets/<DATASET_NAME> and nothing outside of that directory

Documentation

• [ ] I'm adding/editing documentation

Bug fix

• [ ] I'm submitting a bugfix
• [ ] I have added/revised tests related to my bugfix (see the tests folder)

Code cleanup or refactoring

• [ ] I'm refactoring or cleaning up some code