get_security_definition_by_contract_id uses i32 instead of i64

[era127]

I'm not sure if this was intentional in the design, but the FuturesContract and Contract models uses i64 for the conid field, whereas get_security_definition_by_contract_id accepts a vector of i32. Therefore, if you do a search by futures by symbol search you receive i64, and then have to change it to i32 when looking up the security definition.

pub async fn get_security_definition_by_contract_id(
        &self,
        contract_ids: Vec<i32>,
    )
    ...

pub struct FuturesContract {
    pub conid: i64,
     ...

[numberjuani]

fixed