[gnome-shell] build: Remove left-over file

[Florian Müllner <fmuellner src gnome org>]

commit 26dc2a439db62bdc9ce903d8166a279529da51cc
Author: Florian Müllner <fmuellner gnome org>
Date:   Tue Dec 3 00:43:08 2019 +0100

    build: Remove left-over file
    
    The file was generated when importing gnome-extensions-tool from
    a standalone repository. It isn't used by the build system, and
    really shouldn't have ended up in the repository at all.
    
    https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/877

 src/extensions-tool/meson-src.build | 24 ------------------------
 1 file changed, 24 deletions(-)