private static void close(HttpResponseWriter res, Closeable in, Exception cause) {
        close(in);
        res.close(cause);
    }
{@link HttpService} to handle a {@link WebOperation}. Mostly inspired by reactive implementation in
{@link AbstractWebFluxEndpointHandlerMapping}.
spring/boot3-actuator-autoconfigure/src/main/java/com/linecorp/armeria/spring/actuate/WebOperationService.java