Function calculate_msg_b 

fn calculate_msg_b(
    username: &str,
    sign_in_address: &str,
    enrollment_uuid: &str,
    verification_code: &str,
    msg_a: &MsgA,
    client_secret: &[u8; 64],
) -> [u8; 32]

Calculates msgb, the new device’s answer to msga.