gobject-introspection-unwrapped: drop conflicting patch

Without the change `gobject-introspection` fails the build on
`staging-next` as:

    applying patch /nix/store/5w1icwq865fhjs9w2s0vb6xqn5irzxv7-setuptools-74.0-compat.patch
    patching file giscanner/ccompiler.py
    Reversed (or previously applied) patch detected!  Assume -R? [n]
    Apply anyway? [n]
    Skipping patch.
    4 out of 4 hunks ignored -- saving rejects to file giscanner/ccompiler.py.rej
    patching file giscanner/msvccompiler.py
    Reversed (or previously applied) patch detected!  Assume -R? [n]
    Apply anyway? [n]
    Skipping patch.
    1 out of 1 hunk ignored -- saving rejects to file giscanner/msvccompiler.py.rej

pkgs/development/libraries/gobject-introspection/default.nix

@@ -1,7 +1,6 @@
 { stdenv
 , lib
 , fetchurl
-, fetchpatch2
 , glib
 , flex
 , bison
@@ -61,11 +60,6 @@ stdenv.mkDerivation (finalAttrs: {
       src = ./absolute_shlib_path.patch;
       inherit nixStoreDir;
     })
-    (fetchpatch2 {
-      name = "setuptools-74.0-compat.patch";
-      url = "https://github.com/GNOME/gobject-introspection/commit/a2139dba59eac283a7f543ed737f038deebddc19.patch";
-      hash = "sha256-n++wpQuJhAEYtcu8LZDC4+Tx1MYuFIMysFgrvz68jWU=";
-    })
   ] ++ lib.optionals x11Support [
     # Hardcode the cairo shared library path in the Cairo gir shipped with this package.
     # https://github.com/NixOS/nixpkgs/issues/34080