Function client_async_tls 

pub async fn client_async_tls<R, S>(
    request: R,
    stream: S,
) -> Result<(WebSocketStream<MaybeTlsStream<S>>, Response<Option<Vec<u8>>>), Error>
where
    R: IntoClientRequest + Unpin,
    S: 'static + AsyncRead + AsyncWrite + Send + Unpin,
    MaybeTlsStream<S>: Unpin,

Creates a WebSocket handshake from a request and a stream, upgrading the stream to TLS if required.