fix expected value in default config test

charts/k8s-monitoring/charts/feature-pod-logs/tests/default_test.yaml

@@ -58,6 +58,28 @@ tests:
                   target_label = "job"
                 }
 
+                // explicitly set service_name. if not set, loki will automatically try to populate a default.
+                // see https://grafana.com/docs/loki/latest/get-started/labels/#default-labels-for-all-users
+                //
+                // choose the first value found from the following ordered list:
+                // - pod.annotation[resource.opentelemetry.io/service.name]
+                // - pod.label[app.kubernetes.io/name]
+                // - k8s.pod.name
+                // - k8s.container.name
+                rule {
+                  action = "replace"
+                  source_labels = [
+                    "__meta_kubernetes_pod_annotation_resource_opentelemetry_io_service_name",
+                    "__meta_kubernetes_pod_label_app_kubernetes_io_name",
+                    "__meta_kubernetes_pod_name",
+                    "__meta_kubernetes_pod_container_name",
+                  ]
+                  separator = ";"
+                  regex = "^(?:;*)?([^;]+).*$"
+                  replacement = "$1"
+                  target_label = "service_name"
+                }
+
                 // make all labels on the pod available to the pipeline as labels,
                 // they are omitted before write to loki via stage.label_keep unless explicitly set
                 rule {