public static Function<? super HttpService, ThrottlingService>
    newDecorator(ThrottlingStrategy<HttpRequest> strategy,
                 ThrottlingRejectHandler<HttpRequest, HttpResponse> rejectHandler) {
        return builder(strategy).onRejectedRequest(rejectHandler).newDecorator();
    }
Creates a new decorator using the specified {@link ThrottlingStrategy} and
{@link ThrottlingRejectHandler}.

@param strategy The {@link ThrottlingStrategy} instance to define throttling strategy
@param rejectHandler The {@link ThrottlingRejectHandler} instance to define request rejection behaviour
core/src/main/java/com/linecorp/armeria/server/throttling/ThrottlingService.java