Function with_consent_timeout 

pub async fn with_consent_timeout<F, Fut, T>(
    submit: F,
    timeout: Duration,
) -> Result<Result<T, ConsentOutcome>, VtaError>
where
    F: Fn() -> Fut,
    Fut: Future<Output = Result<T, VtaError>>,

with_consent with an explicit deadline. Separate so tests do not sleep for the production timeout.