Add check for 'thelinuxfoundation' user

[caniszczyk]

All CNCF projects require 'thelinuxfoundation' as a user in the project, we should find a way to see if we can check for that

[tegioz]

I think we could make this work with the GitHub API endpoint to get the repository's permission for a given user.

To give this a try we'd need a personal access token from thelinuxfoundation user with scope repo:public_repo.

[caniszczyk]

@tegioz another idea is we are slowly moving more projects to github enterprise

https://github.com/enterprises/cncf

There seems to be an API check for this?
https://docs.github.com/en/rest/reference/orgs#get-an-organization
https://docs.github.com/en/rest/reference/enterprise-admin

It may be in one of those but not sure :/