Function verify_rotation 

pub fn verify_rotation<'a>(
    old: &PublicKeyBundle,
    attestation: &'a RotationAttestation,
) -> Result<&'a PublicKeyBundle>

Verify a rotation attestation against the trusted old public bundle.

On success returns the authenticated successor bundle.

Errors

Error::VerificationFailed if the attestation was not signed by old over its embedded successor.