Use pkgs.nixfmt instead of pkgs.nixfmt-rfc-style

flake.nix

@@ -150,7 +150,7 @@
         in
         {
           ${system}.default = pkgs.mkShell {
-            packages = [ pkgs.nixfmt-rfc-style ];
+            packages = [ pkgs.nixfmt ];
           };
         };
     };