nixos/minetest fix: add missing uid/gid for minetest

nixos/modules/misc/ids.nix

@@ -335,6 +335,7 @@
       kapacitor = 308;
       solr = 309;
       alerta = 310;
+      minetest = 311;
 
       # When adding a uid, make sure it doesn't match an existing gid. And don't use uids above 399!
 
@@ -630,6 +631,7 @@
       kapacitor = 308;
       solr = 309;
       alerta = 310;
+      minetest = 311;
 
       # When adding a gid, make sure it doesn't match an existing
       # uid. Users and groups with the same name should have equal

nixos/modules/services/games/minetest-server.nix

@@ -84,7 +84,9 @@ in
       home            = "/var/lib/minetest";
       createHome      = true;
       uid             = config.ids.uids.minetest;
+      group           = "minetest";
     };
+    users.groups.minetest.gid = config.ids.gids.minetest;
 
     systemd.services.minetest-server = {
       description   = "Minetest Server Service";
@@ -93,6 +95,7 @@ in
 
       serviceConfig.Restart = "always";
       serviceConfig.User    = "minetest";
+      serviceConfig.Group   = "minetest";
 
       script = ''
         cd /var/lib/minetest