Function from_subquery  
pub async fn from_subquery(
    consumer: &impl SubstraitConsumer,
    subquery: &Subquery,
    input_schema: &DFSchema,
) -> Result<Expr, DataFusionError>pub async fn from_subquery(
    consumer: &impl SubstraitConsumer,
    subquery: &Subquery,
    input_schema: &DFSchema,
) -> Result<Expr, DataFusionError>