bug#51876: 28.0.60; Confusing prompt for setting a bookmark

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: 51876@debbugs.gnu.org
> Date: Tue, 16 Nov 2021 09:12:23 +0100
> 
> Perhaps 
> 
>          (if no-overwrite "Set bookmark" "Set bookmark unconditionally")))
> 
> should be
> 
>          (if no-overwrite "Append bookmark" "Set bookmark")))

I would suggest

  (if no-overwrite "Add bookmark named" "Set bookmark named")