Function build_cert 

pub async fn build_cert<TYPES: NodeType, V: Versions, DATAType: Committable + Clone + Eq + Hash + Serialize + Debug + 'static, VOTE: Vote<TYPES, Commitment = DATAType>, CERT: Certificate<TYPES, VOTE::Commitment, Voteable = VOTE::Commitment>>(
    data: DATAType,
    epoch_membership: &EpochMembership<TYPES>,
    view: TYPES::View,
    public_key: &TYPES::SignatureKey,
    private_key: &<TYPES::SignatureKey as SignatureKey>::PrivateKey,
    upgrade_lock: &UpgradeLock<TYPES, V>,
) -> CERT

create certificate

Panics

if we fail to sign the data