Update runtime-class.md

fix Sync doc about Runtime Class
Signed-off-by: LIXIN <xin.li@daocloud.io>

content/zh/docs/concepts/containers/runtime-class.md

@@ -183,6 +183,15 @@ For more details on setting up CRI runtimes, see [CRI installation](/docs/setup/
 
 #### dockershim
 
+<!--
+{{< feature-state for_k8s_version="v1.20" state="deprecated" >}}
+
+Dockershim is deprecated as of Kubernetes v1.20, and will be removed in v1.24. For more information on the deprecation,
+see [dockershim deprecation](/blog/2020/12/08/kubernetes-1-20-release-announcement/#dockershim-deprecation)
+-->
+Dockershim 自 Kubernetes v1.20 起已弃用，并将在 v1.24 中删除。 
+有关弃用的更多信息查看 [dockershim 弃用](/blog/2020/12/08/kubernetes-1-20-release-announcement/#dockershim-deprecation)。
+
 <!--
 RuntimeClasses with dockershim must set the runtime handler to `docker`. Dockershim does not support
 custom configurable runtime handlers.