fix how the metricRequestedForBilling is counted to use queries.size()

Signed-off-by: Perotto <[email protected]>

src/main/java/io/prometheus/cloudwatch/GetMetricDataDataGetter.java

@@ -67,7 +67,7 @@ private List<MetricDataQuery> buildMetricDataQueries(
         queries.add(query);
       }
     }
-    metricRequestedForBilling += stats.size();
+    metricRequestedForBilling += queries.size();
     return queries;
   }