You can identify requests from Github's free CI reliably which probably covers 99% of requests.
For example GMP blocked GitHub:
https://www.theregister.com/2023/06/28/microsofts_github_gmp...
This "emergency measure" is still in place, but there are mirrors available so it doesn't actually matter too much.
I try to stick to GitHub for GitHub CI downloads.
E.g. my SQLite project downloads code from the GitHub mirror rather than Fossil.