[llvm] [CI] Make email check workflow fail when author's email is private in Github UI (PR #148694)

[David Spickett via llvm-commits]

DavidSpickett wrote:

I think @boomanaiden154 has the technical aspects covered, they can be the approver.

The new description is much clearer, thankyou!

> Due to this, the email check workflow passes even when the author's email is private in Github.

This might explain why I've seen a number of noreply addresses slip through.

https://github.com/llvm/llvm-project/pull/148694