Function query_candid 

pub fn query_candid<Input, Output>(
    env: &PocketIc,
    canister_id: CanisterId,
    method: &str,
    input: Input,
) -> Result<Output, ClientError>
where
    Input: ArgumentEncoder,
    Output: for<'a> ArgumentDecoder<'a>,

Call a canister candid query method, anonymous.