
Make sure that the user and password are correct:
let rpc_url = "http://172.14.198.19:18444";
let rpc = Client::new(rpc_url, Auth::UserPass("bitcoin_regtest".to_string(), "1".to_string()))
.unwrap();
let block_height = rpc.get_block_count().unwrap();
println!("Current block height: {}", block_height);