Dot-Project: backfill `maintainers.csv` from `.project/maintainers.yml` when applicable

[ahmadqasembader]

For the Orgs that has adopted the .project, we should backfill the maintainers.csv file untill the adoption of .project is complete across all CNCF Orgs.

Once the org has adopted the .project, it replaces the csv file, however, during the adoption process of .project, we need to maintain resouces access in a unifed place.

[riaankleinhans]

@ahmadqasembader I have created a project-maintainers.json file in a private repo that contain all the verified project's maintainers.
I will make a GHA that periodically make a PR to update the project-maintainers.csv file.

[lizrice]

At some point the text here will need updating to reflect that projects just maintain their .project/maintainers.yaml file rather than update the CSV file here by PR (if I understand correctly)

[ahmadqasembader]

Correct @lizrice -- Will handle it. Thanks

#1509

[ahmadqasembader]

Closing. New projects with .project repos are automated via maintainers-manager private repo, and the new automated CSV file is available in cncf/foundation -> project-maintainers-.project.csv