set nixpkgs rev in version

flake.nix

@@ -42,6 +42,8 @@
 
         # include git rev of this repo/flake into the nixos-version
         system.configurationRevision = nixpkgs.lib.mkIf (self ? rev) self.rev;
+        system.nixos.revision = nixpkgs.rev;
+        system.nixos.versionSuffix = "-${lib.substring 0 8 nixpkgs.rev}";
         # set nixpkgs on the target to the nixpkgs version of the deployment
         nix.registry.nixpkgs.flake = nixpkgs;
         nix.nixPath = lib.mkForce [ "nixpkgs=${nixpkgs}" "nixos-config=/dontuse" ];