nixos/mate: allow remove any added package

Only extra packages removable currently, but it's possible to run MATE without packages like caja or yelp

nixos/modules/services/x11/desktop-managers/mate.nix

@@ -74,11 +74,9 @@ in
     # Debugging
     environment.sessionVariables.MATE_SESSION_DEBUG = mkIf cfg.debug "1";
 
-    environment.systemPackages =
-      pkgs.mate.basePackages ++
-      (pkgs.gnome.removePackagesByName
-        pkgs.mate.extraPackages
-        config.environment.mate.excludePackages) ++
+    environment.systemPackages = pkgs.gnome.removePackagesByName
+      (pkgs.mate.basePackages ++
+      pkgs.mate.extraPackages ++
       [
         pkgs.desktop-file-utils
         pkgs.glib
@@ -87,7 +85,8 @@ in
         pkgs.xdg-user-dirs # Update user dirs as described in https://freedesktop.org/wiki/Software/xdg-user-dirs/
         pkgs.mate.mate-settings-daemon
         pkgs.yelp # for 'Contents' in 'Help' menus
-      ];
+      ])
+      config.environment.mate.excludePackages;
 
     programs.dconf.enable = true;
     # Shell integration for VTE terminals