tools: update nixpkgs-unstable to ab72be9733b41190ea34f1422a3e4e243ed

Author: panva

tools/nix/pkgs.nix

@@ -1,21 +1,10 @@
 arg:
 let
   repo = "https://github.com/NixOS/nixpkgs";
-  rev = "13043924aaa7375ce482ebe2494338e058282925";
+  rev = "ab72be9733b41190ea34f1422a3e4e243ede7533";
   nixpkgs = import (builtins.fetchTarball {
     url = "${repo}/archive/${rev}.tar.gz";
-    sha256 = "1pbv1c3syp94rh147s2nhbzfcib01blz3s7g290m43s3nk71404z";
+    sha256 = "1a720dxki2ymwiwdjn8awgpinigz5wsnxg2mmpy1s2b2wyy3gmz1";
   }) arg;
 in
 nixpkgs
-// {
-  nixfmt-tree = nixpkgs.nixfmt-tree.overrideAttrs (old: {
-    patches = (old.patches or [ ]) ++ [
-      (nixpkgs.fetchpatch2 {
-        url = "https://github.com/numtide/treefmt/commit/b96016b4e38ffc76518087b3b0c9bbfa190d5225.patch?full_index=1";
-        revert = true;
-        hash = "sha256-DcxT2OGPX6Kmxhqa56DjZsSh2hoyhPyVmE17ULeryv8=";
-      })
-    ];
-  });
-}