feat: Onboard EPA historical air quality dataset

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Description

Included:
Annual summaries
CO Daily Summary
CO Hourly Summary
HAP Daily Summary
HAP Hourly Summary
Lead Daily Summary
NO2 Daily Summary
NO2 Hourly Summary
NONOxNOy Daily Summary
NONOxNOy Hourly Summary
Ozone Daily Summary
Ozone Hourly Summary
PM 10 Daily Summary
PM10 Hourly Summary
PM25 Frm Hourly Summary
PM25 NonFrm Daily Summary
PM25 NonFrm Hourly Summary
PM25 Speciation Daily Summary
PM25 Speciation Hourly Summary
Pressure Daily Summary
Pressure Hourly Summary
RH and DP Daily Summary
RH and DP Hourly Summary
SO2 Daily Summary
SO2 Hourly Summary
Temperature Daily Summary
Temperature Hourly Summary
VOC Daily Summary
VOC Hourly Summary
Wind Daily Summary
Wind Hourly Summary

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/epa_historical_air_quality and nothing outside of that directory.
• This PR is appropriately labeled.

[nlarge-google]

@adlersantos Ready for review. Thanks!

[adlersantos]

Looks good in general. Just a few comments.

[nlarge-google]

@adlersantos I have done research into trying to understand why this PR keeps failing at the Run Tests point. Is there some recent change to the code behind these checks? What changes do I need to make to ensure that these checks pass?
It looks like other developers PRs are experiencing the same issue and it is not just this one.

Thanks!

[nlarge-google]

@adlersantos I dont see any button in github UI that allows me to rerun the checks without making code changes, so I had to close and reopen the PR in order to trigger the tests. If you know a better way to re-trigger the checks, or if closing and re-opening the PR is acceptable then please let me know.

[nlarge-google]

@adlersantos Please review this code at your earliest convenience. Thanks!

[nlarge-google]

@adlersantos I have made the changes. Please review. Thanks.

[nlarge-google]

@adlersantos All requested changes are completed. Please review again. Thanks!

[adlersantos]

Thanks a lot!