Onboard Pipelines:

1)census_opportunity_atlas.tract_covariates

Based on #

Note: It's recommended to open an issue first for context and discussion.

Checklist

Note: Delete items below that aren't applicable to your pull request.

• Please merge this PR for me once it is approved.
• If this PR adds or edits a dataset or pipeline, it was reviewed and approved by the Google Cloud Public Datasets team beforehand.
• If this PR adds or edits a dataset or pipeline, I put all my code inside datasets/<census_opportunity_atlas and nothing outside of that directory.
• This PR is appropriately labeled.