Don't arbitrarily choose the largest datapoint

pkg/scalers/graphite_scaler.go

@@ -195,16 +195,10 @@ func (s *graphiteScaler) ExecuteGrapQuery() (float64, error) {
 		return -1, fmt.Errorf("graphite query %s returned multiple series", s.metadata.query)
 	}
 
-	var v float64 = -1
-	for _, datapoints := range result[0].Datapoints {
-		if strconv.FormatFloat(datapoints[0], 'f', -1, 64) != "" {
-			if datapoints[0] > v {
-				v = datapoints[0]
-			}
-		}
-	}
+	// https://graphite-api.readthedocs.io/en/latest/api.html#json
+	datapoint := result[0].Datapoints[0][0]
 
-	return v, nil
+	return datapoint, nil
 }
 
 func (s *graphiteScaler) GetMetrics(ctx context.Context, metricName string, metricSelector labels.Selector) ([]external_metrics.ExternalMetricValue, error) {