[ event_reporter ]: fixes after pr review

event_reporter/reporter/application_event_reporter.go

@@ -39,6 +39,8 @@ var (
 	resourceEventCacheExpiration = time.Minute * time.Duration(env.ParseNumFromEnv(argocommon.EnvResourceEventCacheDuration, 20, 0, math.MaxInt32))
 )
 
+const ApplicationKind = "Application"
+
 type applicationEventReporter struct {
 	cache                    *servercache.Cache
 	codefreshClient          codefresh.CodefreshClient
@@ -216,7 +218,7 @@ func (s *applicationEventReporter) StreamApplicationEvents(
 			return err
 		}
 		reconcileDuration := time.Since(startTime)
-		s.metricsServer.ObserveEventProcessingDurationHistogramDuration(a.Name, "Application", metrics.MetricChildAppEventType, reconcileDuration)
+		s.metricsServer.ObserveEventProcessingDurationHistogramDuration(a.Name, ApplicationKind, metrics.MetricChildAppEventType, reconcileDuration)
 	} else {
 		logCtx.Info("processing as root application")
 		// will get here only for root applications (not managed as a resource by another application)
@@ -237,7 +239,7 @@ func (s *applicationEventReporter) StreamApplicationEvents(
 			return fmt.Errorf("failed to send event for root application %s/%s: %w", a.Namespace, a.Name, err)
 		}
 		reconcileDuration := time.Since(startTime)
-		s.metricsServer.ObserveEventProcessingDurationHistogramDuration(a.Name, "Application", metrics.MetricParentAppEventType, reconcileDuration)
+		s.metricsServer.ObserveEventProcessingDurationHistogramDuration(a.Name, ApplicationKind, metrics.MetricParentAppEventType, reconcileDuration)
 	}
 
 	revisionMetadata, _ := s.getApplicationRevisionDetails(ctx, a, getOperationRevision(a))