[expo-cli] use correct description for openDevToolsAtStartup in the ? message

[SConaway]

I noticed that the message triggered by entering ? in the expo start command displays the wrong value of openDevToolsAtStartup.

Here's what it shows:

Automatically opening DevTools disabled.
Press d to open DevTools now.

 Expo  Press ? to show a list of all available commands.

 › Press a | open Android
 › shift+a | select a device or emulator
 › Press i | open iOS simulator
 › shift+i | select a simulator
 › Press w | open web

 › Press o | open project code in your editor
 › Press c | show project QR
 › Press p | toggle build mode (development)
 › Press r | restart bundler
 › shift+r | restart and clear cache

 › Press d | open Expo DevTools
 › shift+d | toggle auto opening DevTools on startup (enabled)
 › Press e | share the app link by email
 › Press s | sign out (@sconaway)