fix(test): allow for summary and histogram types to be emit

Author: daveoy

pkg/util/metrics/helpers.go

@@ -58,6 +58,10 @@ func ParsePrometheusMetrics(metricsText string) ([]Float64MetricRepresentation,
 				value = *metric.Counter.Value
 			case pcm.MetricType_GAUGE:
 				value = *metric.Gauge.Value
+			case pcm.MetricType_SUMMARY:
+				value = *metric.Summary.SampleSum
+			case pcm.MetricType_HISTOGRAM:
+				value = *metric.Histogram.SampleSum
 			default:
 				return metrics, fmt.Errorf("unexpected MetricType %s for metric %s",
 					pcm.MetricType_name[int32(*metricFamily.Type)], *metricFamily.Name)