nixos-module/server/lxc-containers: use switch-to-configuration in ExecReload

nix/nixos-module/server/lxc-containers.nix

@@ -174,7 +174,7 @@ in
             #! ${pkgs.runtimeShell} -e
 
             SYSTEM=$(dirname $(readlink /var/lib/lxc/$1/rootfs/init))
-            exec ${pkgs.lxc}/bin/lxc-attach -n $1 $SYSTEM/activate
+            exec ${pkgs.lxc}/bin/lxc-attach -n $1 $SYSTEM/bin/switch-to-configuration switch
           '';
         in
           "${script} %i";