GitHub doesn't use Azure yet, but has just published their migration path to azure a few days ago.

I would link to that article, but that one does seem down ;)

At least some bits of it do. I was writing something to pull logs the other day and the redirect was to an azure bucket. It also returned a 401 with the valid temporary authed redirect in the header. I was a bit worried I'd found a massive security hole but it appears after some testing it just returned the wrong status code.

I only noticed it because VSCode's updater failed.