Function perform_cpace 

pub(super) async fn perform_cpace(
    username: &str,
    sign_in_address: &str,
    sign_in_token: &str,
    enrollment_uuid: &str,
    verification_code: &str,
    rest: &RestClient,
    timing: &Timing,
) -> Result<CredentialBundle, OnePasswordError>

Runs the whole exchange over rest with a fresh random client secret and returns the credentials the enrolled device shared.