Fix indent typo.

chusiang · chusiang · commit e0260a69c590 · 2020-08-28T00:16:14.000+08:00
diff --git a/12.which-are-the-commonly-used-modules.md b/12.which-are-the-commonly-used-modules.md
@@ -253,7 +253,7 @@
      file:
        path: /home/docker/.vimrc
        state: touch
-	 		mode: "u=rw,g=r,o=r"
+       mode: "u=rw,g=r,o=r"
      when: stat_vimrc.stat.exists == false
    ```
 
