Fixed formatting for markdown file (#12192)

* Fixed formatting for markdown file

File updated: define-environment-variable-container.md
Language: zh

* Fixes to markdown formatting

content/zh/docs/tasks/inject-data-application/define-environment-variable-container.md

@@ -30,32 +30,44 @@ content_template: templates/task
 
 1. 基于YAML文件创建一个Pod:
 
-       kubectl create -f https://k8s.io/docs/tasks/inject-data-application/envars.yaml
+    ```shell
+    kubectl create -f https://k8s.io/docs/tasks/inject-data-application/envars.yaml
+    ```
 
 1. 获取一下当前正在运行的Pods信息:
 
-       kubectl get pods -l purpose=demonstrate-envars
+    ```shell
+    kubectl get pods -l purpose=demonstrate-envars
+    ```
 
     查询结果应为:
 
-        NAME            READY     STATUS    RESTARTS   AGE
-        envar-demo      1/1       Running   0          9s
+    ```log
+    NAME            READY     STATUS    RESTARTS   AGE
+    envar-demo      1/1       Running   0          9s
+    ```
 
 1. 进入该Pod下的容器并打开一个命令终端:
 
-       kubectl exec -it envar-demo -- /bin/bash
+    ```shell
+    kubectl exec -it envar-demo -- /bin/bash
+    ```
 
 1. 在命令终端中通过执行`printenv`打印出环境变量。
 
-       root@envar-demo:/# printenv
+    ```shell
+    root@envar-demo:/# printenv
+    ```
 
     打印结果应为:
 
-        NODE_VERSION=4.4.2
-        EXAMPLE_SERVICE_PORT_8080_TCP_ADDR=10.3.245.237
-        HOSTNAME=envar-demo
-        ...
-        DEMO_GREETING=Hello from the environment
+    ```log
+    NODE_VERSION=4.4.2
+    EXAMPLE_SERVICE_PORT_8080_TCP_ADDR=10.3.245.237
+    HOSTNAME=envar-demo
+    ...
+    DEMO_GREETING=Hello from the environment
+    ```
 
 1. 通过键入`exit`退出命令终端。