Function post 

pub async fn post<U>(
    uri: U,
    body: IpcBytes,
) -> Result<Response, Box<dyn Error + Sync + Send>>
where
    U: TryInto<Uri>,
    Box<dyn Error + Sync + Send>: From<<U as TryInto<Uri>>::Error>,

Send a POST request to the uri with a given request body.

The http_client is used to send the request.