The key was revoked. If it was revoked as part of a rotation you
were given a replacement and a grace period, and that period has
now ended — deploy the new key. GET /v1/me on a still-valid key
reports revokes_at during a grace period, which is the signal to
act before seeing this error.
Switch on the code member — api_key_revoked — which is
stable. Do not parse the type URI: it points here, and where
"here" is may change.