[zh-cn]sync kubeadm_certs_renew kubeadm_certs/_index

Signed-off-by: xin.li <xin.li@daocloud.io>

content/zh-cn/docs/reference/setup-tools/kubeadm/generated/kubeadm_certs/_index.md

@@ -1,5 +1,5 @@
 <!--
-Commands related to handling kubernetes certificates
+Commands related to handling Kubernetes certificates
 -->
 处理 Kubernetes 证书的相关命令。
 
@@ -9,7 +9,7 @@ Commands related to handling kubernetes certificates
 ### 概要
 
 <!--
-Commands related to handling kubernetes certificates
+Commands related to handling Kubernetes certificates
 -->
 处理 Kubernetes 证书相关的命令。
 

content/zh-cn/docs/reference/setup-tools/kubeadm/generated/kubeadm_certs/kubeadm_certs_renew.md

@@ -9,9 +9,9 @@ Renew certificates for a Kubernetes cluster
 ### 概要
 
 <!--
-This command is not meant to be run on its own. See list of available subcommands.
+Renew certificates for a Kubernetes cluster
 -->
-此命令并非设计用来单独运行。请参阅可用子命令列表。
+为 Kubernetes 集群更新证书
 
 ```
 kubeadm certs renew [flags]