Remove redundant Prometheus variable labels (#5008) (#5085)

Remove redundant variable labels

Signed-off-by: Haywood Shannon <5781935+haywoodsh@users.noreply.github.com>
(cherry picked from commit fb60fb6)

cmd/nginx-ingress/main.go

@@ -699,10 +699,8 @@ func createPlusAndLatencyCollectors(
 
 			serverZoneVariableLabels := []string{"resource_type", "resource_name", "resource_namespace"}
 			streamServerZoneVariableLabels := []string{"resource_type", "resource_name", "resource_namespace"}
-			cacheZoneLabels := []string{"resource_type", "resource_name", "resource_namespace"}
-			workerPIDVariableLabels := []string{"resource_type", "resource_name", "resource_namespace"}
 			variableLabelNames := nginxCollector.NewVariableLabelNames(upstreamServerVariableLabels, serverZoneVariableLabels, upstreamServerPeerVariableLabelNames,
-				streamUpstreamServerVariableLabels, streamServerZoneVariableLabels, streamUpstreamServerPeerVariableLabelNames, cacheZoneLabels, workerPIDVariableLabels)
+				streamUpstreamServerVariableLabels, streamServerZoneVariableLabels, streamUpstreamServerPeerVariableLabelNames, nil, nil)
 			promlogConfig := &promlog.Config{}
 			logger := promlog.New(promlogConfig)
 			plusCollector = nginxCollector.NewNginxPlusCollector(plusClient, "nginx_ingress_nginxplus", variableLabelNames, constLabels, logger)