The test public key used in these tests is a key that I just generated
specifically for this purpose. I deleted the associated private key, so
even if someone accidentally left this attached to their account, it
should have no effect. Of course, I have no way of actually proving
that I deleted the private key, so uh... yeah. All the more reason to
never run these integration tests using a "real" GitHub account, always
use a dedicated test account.