Fix doc (#9107)

daemon_iex is a command, not a "comment".

Author: leandrocp

lib/mix/lib/mix/tasks/release.ex

@@ -125,7 +125,7 @@ defmodule Mix.Tasks.Release do
 
   ### Daemon mode (Unix-like)
 
-  You can run the release in daemon mode written as a comment:
+  You can run the release in daemon mode with the command:
 
       bin/RELEASE_NAME daemon_iex