fix link to google shellguide

Author: icy

README.md

@@ -636,7 +636,7 @@ See also in `LESSONS.md` (https://github.com/icy/bash-coding-style/blob/master/L
 ## Resources
 
 * [Anybody can write good bash with a little effort](https://blog.yossarian.net/2020/01/23/Anybody-can-write-good-bash-with-a-little-effort)
-* [Google - Shell Style Guide](https://google.github.io/styleguide/shell.xml)
+* [Google - Shell Style Guide](https://github.com/google/styleguide/blob/gh-pages/shellguide.md)
 * [Defensive Bash programming](https://news.ycombinator.com/item?id=7815190)
 * [Shellcheck](https://github.com/koalaman/shellcheck)