Feat add sync action

[aditigopalan]

Fixes #97

This GitHub Action automates the process of syncing a specified Google Sheet to a GitHub repository as a CSV file, facilitating RFC integration.

Key Features:

1. Daily Automation: Runs on a schedule (cron) or can be triggered manually.
2. Customizable Inputs:
   • spreadsheet_id: The Google Sheet ID to monitor.
   • stop_day and stop_time: Defines when the action should stop execution.
3. Branch and PR Management:
   • Creates a branch named RFC-{GoogleSheetName}.
   • Stores the CSV as RFC_DATA/{GoogleSheetName}.csv.
   • Ensures a single pull request (PR) for the branch, reusing it for subsequent changes.
4. Secure Credentials:
   • Uses RFC_TOKEN (Personal Access Token) and GOOGLE_CREDENTIALS stored securely as GitHub Secrets.

Workflow:

1. Checks for changes in the Google Sheet.
2. Updates the CSV file in the RFC_DATA folder on the corresponding branch.
3. Updates or creates a pull request for the branch.

Script is tested and RFC Integration works, but test on actual action pending merge

Note: I used Google credentials from HTAN. Does MC2 have a google service account? If so those credentials should be updated.

The end result will look something like #164

[vpchung]

LGTM.

I just have some nitpicks 🙃

[aditigopalan]

LGTM.

I just have some nitpicks 🙃

Thank you so much! Let me know if the fixes make sense :)