gnome: rename from gnome3

Since GNOME version is now 40, it no longer makes sense to use the old attribute name.

pkgs/development/libraries/gtkmm/3.x.nix

@@ -1,4 +1,4 @@
-{ lib, stdenv, fetchurl, pkg-config, meson, ninja, python3, gtk3, glibmm, cairomm, pangomm, atkmm, epoxy, gnome3 }:
+{ lib, stdenv, fetchurl, pkg-config, meson, ninja, python3, gtk3, glibmm, cairomm, pangomm, atkmm, epoxy, gnome }:
 
 stdenv.mkDerivation rec {
   pname = "gtkmm";
@@ -22,7 +22,7 @@ stdenv.mkDerivation rec {
   doCheck = false;
 
   passthru = {
-    updateScript = gnome3.updateScript {
+    updateScript = gnome.updateScript {
       packageName = pname;
       attrPath = "${pname}3";
       versionPolicy = "odd-unstable";

pkgs/development/libraries/gtkmm/4.x.nix

@@ -10,7 +10,7 @@
 , cairomm_1_16
 , pangomm_2_48
 , epoxy
-, gnome3
+, gnome
 , makeFontsConf
 , xvfb_run
 }:
@@ -65,7 +65,7 @@ stdenv.mkDerivation rec {
   '';
 
   passthru = {
-    updateScript = gnome3.updateScript {
+    updateScript = gnome.updateScript {
       packageName = pname;
       attrPath = "${pname}4";
       versionPolicy = "odd-unstable";