Switching from compilation mode to inf-ruby

[mjsteger]

Is there any reason that minitest-emacs isn't included in inf-ruby's list of modes to add inf-ruby-switch-from-compilation to the keymap? It's pretty easy to add the keybinding manually, but I was just curious if this was a conscious omission, and if not, if it'd be okay to make a PR over there and/or add some extra code here to add the keybinding.