The Open in External Editor button makes editing a game INI file easy,
and the Refresh button is only useful if you edit the game INI. You're
not supposed to edit read-only game INIs, so let's not show these two
buttons for read-only game INIs.
I implemented this by hiding the buttons instead of not creating them in
the first place so we don't have to branch on whether the buttons exist
in GameConfigEdit::ConnectWidgets.