chore(nix): follow system release channel (#9784)

In order to avoid glibc mismatches, the dev-shell started by the nix
flake should follow the system channel instead of pinning a version by
itself.

scripts/nix/flake.lock

@@ -2,16 +2,15 @@
   "nodes": {
     "nixpkgs": {
       "locked": {
-        "lastModified": 1744309437,
-        "narHash": "sha256-QZnNHM823am8apCqKSPdtnzPGTy2ZB4zIXOVoBp5+W0=",
+        "lastModified": 1751498133,
+        "narHash": "sha256-QWJ+NQbMU+NcU2xiyo7SNox1fAuwksGlQhpzBl76g1I=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "f9ebe33a928b5d529c895202263a5ce46bdf12f7",
+        "rev": "d55716bb59b91ae9d1ced4b1ccdea7a442ecbfdb",
         "type": "github"
       },
       "original": {
         "id": "nixpkgs",
-        "ref": "nixos-24.11",
         "type": "indirect"
       }
     },

scripts/nix/flake.nix

@@ -1,6 +1,6 @@
 {
   inputs = {
-    nixpkgs.url = "nixpkgs/nixos-24.11";
+    nixpkgs.url = "nixpkgs";
     nixpkgs-unstable.url = "github:nixos/nixpkgs/nixos-unstable";
   };
 
@@ -29,8 +29,7 @@
         openssl_3
         glib
         gtk3
-        libsoup
-        webkitgtk
+        libsoup_3
         librsvg
         zenity
         desktop-file-utils