Merge pull request kubernetes#47553 from my-git9/pp-29355

[zh-cn] sync kubelet-separate-disk-gc.md

Author: k8s-ci-robot

Diff for: content/zh-cn/docs/reference/command-line-tools-reference/feature-gates/kubelet-separate-disk-gc.md

@@ -9,10 +9,15 @@ stages:
   - stage: alpha 
     defaultValue: false
     fromVersion: "1.29"
+    toVersion: "1.30"
+  - stage: beta
+    defaultValue: true
+    fromVersion: "1.31"
 ---
 
 <!--
-Enable kubelet to garbage collect container images and containers
-even when those are on a separate filesystem.
+The split image filesystem feature enables kubelet to perform garbage collection
+of images (read-only layers) and/or containers (writeable layers) deployed on
+separate filesystems.
 -->
-启用 kubelet，即使在容器镜像和容器位于独立文件系统的情况下，也能进行垃圾回收。
+分离镜像文件系统特性使 kubelet 能够对部署在不同文件系统上的镜像（只读层）和/或容器（可写层）执行垃圾回收。