[zh] Update pod-configmap-env-var-valueFrom.md

Signed-off-by: xin.li <[email protected]>

Author: my-git9

content/zh/examples/pods/pod-configmap-env-var-valueFrom.yaml

@@ -6,7 +6,7 @@ spec:
   containers:
     - name: test-container
       image: k8s.gcr.io/busybox
-      command: [ "/bin/sh", "-c", "echo $(SPECIAL_LEVEL_KEY) $(SPECIAL_TYPE_KEY)" ]
+      command: [ "/bin/echo", "$(SPECIAL_LEVEL_KEY) $(SPECIAL_TYPE_KEY)" ]
       env:
         - name: SPECIAL_LEVEL_KEY
           valueFrom: