feat: add auto-upgrade to andhrimnir and nanna

modules/hosts/andhrimnir/configuration.nix

···
         grub
         nvidia-gpu
         kde-desktop
+        auto-upgrade
         neoxa
         (autoLogin "neoxa")
       ];

modules/hosts/nanna/configuration.nix

···
       with inputs.self.nixosModules;
       with inputs.self.factory;
       [
-        systemd-boot
+        inputs.nixos-hardware.nixosModules.lenovo-legion-15ich
+        grub
         budgie-desktop
-        inputs.nixos-hardware.nixosModules.lenovo-legion-15ich
+        auto-upgrade
         juliette
       ];