code: public static <T> RateLimiterOperator<T> of(RateLimiter rateLimiter, Scheduler scheduler) {
          return new RateLimiterOperator<>(rateLimiter, scheduler);
      }
docs: Creates a RateLimiterOperator.
  
  @param <T>         the value type of the upstream and downstream
  @param rateLimiter the Rate limiter
  @param scheduler   the {@link Scheduler} where to publish
  @return a RateLimiterOperator