[zh] Update blog/kubernetes-1-20-release-announcement.md

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

Author: my-git9

content/zh/blog/_posts/2020-12-08-kubernetes-release-1.20.md

@@ -3,13 +3,15 @@ layout: blog
 title: 'Kubernetes 1.20: 最新版本'
 date: 2020-12-08
 slug: kubernetes-1-20-release-announcement
+evergreen: true
 ---
 
 <!-- ---
 layout: blog
 title: 'Kubernetes 1.20: The Raddest Release'
 date: 2020-12-08
 slug: kubernetes-1-20-release-announcement
+evergreen: true
 --- -->
 
 **作者:** [Kubernetes 1.20 发布团队](https://github.com/kubernetes/sig-release/blob/master/releases/release-1.20/release_team.md)