feat: Onboarding COVID-19 (UK) Government Response dataset

[dipannitab2392]

Description

Pipeline included :

• covid19_govt_response/oxford_policy_tracker

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Checklist

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• 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/covid19_govt_response and nothing outside of that directory.
• This PR is appropriately labeled.

[google-cla]

☹️ Sorry, but only Googlers may change the label cla: yes.