[seahorse] Remove AUTHORS

[Niels De Graef <nielsdg src gnome org>]

commit ce1c955e1b7e08887c99bb180c0eaf5cdfaa823b
Author: Niels De Graef <nielsdegraef gmail com>
Date:   Mon May 23 20:24:21 2022 +0200

    Remove AUTHORS
    
    It's woefully out-of-date, with most people in there not having
    contributed for over a decade. We still have a THANKS file and the git
    changelog anwyay.

 AUTHORS | 14 --------------
 1 file changed, 14 deletions(-)