public static Function<? super HttpClient, RetryingClient> newDecorator(RetryRule retryRule) {
        return builder(retryRule).newDecorator();
    }
Creates a new {@link HttpClient} decorator that handles failures of an invocation and retries HTTP
requests.

@param retryRule the retry rule
core/src/main/java/com/linecorp/armeria/client/retry/RetryingClient.java