@Override
    public int hashCode() {
      int result = rule != null ? rule.hashCode() : 0;
      result = 31 * result + (tagBasedResourceIds != null ? tagBasedResourceIds.hashCode() : 0);
      return result;
    }
Add a MetricRule to be used to configure a custom TTL using the value from {@link
MetricRule#listMetricsCacheTtl} to override the default expiry

@param metricRule
@return this
src/main/java/io/prometheus/cloudwatch/CachingDimensionSource.java