Change announcement to 0

Author: azuchi

_posts/ja/posts/2021-09-29-release-0.21.2.md

@@ -10,7 +10,7 @@ layout: post
 version: 1
 
 ## Only true if release announcement or security annoucement.  English posts only
-announcement: 1
+announcement: 0
 
 excerpt: >
   Bitcoin Core 0.21.2 が利用可能になりました。