docs: @Benchmark
    @BenchmarkMode(Mode.SampleTime)
    @OutputTimeUnit(TimeUnit.NANOSECONDS)
    public CallOptions withOption() {
      CallOptions opts = CallOptions.DEFAULT;
      for (int i = 0; i < customOptions.size(); i++) {
        opts = opts.withOption(customOptions.get(i), "value");
      }
      return opts;
    }