private static HttpResponse respond(CompletableFuture<HttpResponse> future, Disposable disposable) {
        final HttpResponse response = HttpResponse.of(future);
        response.whenComplete().exceptionally(cause -> {
            disposable.dispose();
            return null;
        });
        return response;
    }
Creates a new {@link ResponseConverterFunction} instance.

@param responseConverter the function which converts an object with the configured
                         {@link ResponseConverterFunction}
rxjava2/src/main/java/com/linecorp/armeria/server/rxjava2/ObservableResponseConverterFunction.java