docs: public static ExpiryPolicy<Object, Object> timeToIdleExpiration(Duration timeToIdle) {
      Objects.requireNonNull(timeToIdle, "TTI duration cannot be null");
      if (timeToIdle.isNegative()) {
        throw new IllegalArgumentException("TTI duration cannot be negative");
      }
      return new TimeToIdleExpiryPolicy(timeToIdle);
    }