public LoggingRpcClient build(RpcClient delegate) {
        return new LoggingRpcClient(delegate, logWriter(), successSampler(), failureSampler());
    }
Returns a newly-created {@link LoggingRpcClient} decorating {@code delegate} based on the properties of
this builder.
core/src/main/java/com/linecorp/armeria/client/logging/LoggingRpcClientBuilder.java