Fix: selector's Indentation (#4825)

correct the selector's Indentation in file `logging-stack.yaml`.

content_zh/docs/tasks/telemetry/logs/fluentd/index.md

@@ -54,7 +54,7 @@ spec:
   - port: 9200
     protocol: TCP
     targetPort: db
-    selector:
+  selector:
     app: elasticsearch
 ---
 # Elasticsearch Deployment
@@ -117,7 +117,7 @@ spec:
     port: 24224
     protocol: UDP
     targetPort: 24224
-    selector:
+  selector:
     app: fluentd-es
 ---
 # Fluentd Deployment
@@ -202,7 +202,7 @@ spec:
   - port: 5601
     protocol: TCP
     targetPort: ui
-    selector:
+  selector:
     app: kibana
 ---
 # Kibana Deployment
@@ -360,4 +360,4 @@ Created config rule/istio-system/newlogtofluentd at revision 22376
     $ killall kubectl
     {{< /text >}}
 
-* 如果您不打算探索任何后续任务，请参考 [Bookinfo 清理](/zh/docs/examples/bookinfo/#清理)中的指示停止应用程序。
+* 如果您不打算探索任何后续任务，请参考 [Bookinfo 清理](/zh/docs/examples/bookinfo/#清理)中的指示停止应用程序。