nixos/gdm: Remove stray `with pkgs.gnome;`

It was unused – `gdm` is part of the outer scope.

Changed files
+1 -1
nixos
modules
services
x11
display-managers
+1 -1
nixos/modules/services/x11/display-managers/gdm.nix
···
];
# Otherwise GDM will not be able to start correctly and display Wayland sessions
-
systemd.packages = with pkgs.gnome; [
+
systemd.packages = [
gdm
pkgs.gnome-session
pkgs.gnome-shell