public static ClientDecoration of(DecoratingHttpClientFunction decorator) {
        return builder().add(decorator).build();
    }
Creates a new instance from a single {@link DecoratingHttpClientFunction}.

@param decorator the {@link DecoratingHttpClientFunction} that transforms an {@link HttpClient}
                 to another
core/src/main/java/com/linecorp/armeria/client/ClientDecoration.java