Function subscribe 

pub async fn subscribe(
    client: &Arc<FutuClient>,
    symbols: &[String],
    sub_types: &[i32],
    is_first_push: bool,
    is_reg_push: bool,
    extended_time: Option<bool>,
    session: Option<i32>,
    is_sub_order_book_detail: Option<bool>,
) -> Result<String>

对齐 Python SDK OpenQuoteContext.subscribe。