conf: fix wrong default example value

conf/app.ini

@@ -72,7 +72,7 @@ ENABLE_GZIP = false
 LANDING_PAGE = home
 
 [repository]
-; Root path for storing repositories's data, default is "~/<username>/gogs-repositories"
+; Root path for storing repositories's data, default is "~/gogs-repositories"
 ROOT =
 ; The script type server supports, sometimes could be "sh"
 SCRIPT_TYPE = bash