bug#55940: macOS: <ns-show-prefs> displayed as keybinding for \\[customize]

[Stefan Kangas]

Lars Ingebrigtsen <larsi@gnus.org> writes:

> It would be easy enough to add a block-list
> mechanism for `substitute-command-keys', but it seems a bit hacky.

Does it make sense to just never show any such events with \\[foo]
substitutions?  I think we want "real" keybindings, not events.here.
If only event "keys" are available, I think we should better display
"M-x foo" instead.