improve output of errors

[arsenii-firebolt]

➤  fb select 42
Failed to send the request: error sending request for url (http://localhost:9123/?&output_format=PSQL): client error (Connect)
Time: 5.1ms

instead of

➤  fb select 42
Failed to send the request: reqwest::Error { kind: Request, url: Url { scheme: "http", cannot_be_a_base: false, username: "", password: None, host: Some(Domain("localhost")), port: Some(9123), path: "/", query: Some("&output_format=PSQL"), fragment: None }, source: Error { kind: Connect, source: Some(ConnectError("tcp connect error", Os { code: 111, kind: ConnectionRefused, message: "Connection refused" })) } }
Time: 4.9ms