nixos/heapster: define group, fix after #133166

nixos/modules/misc/ids.nix

@@ -244,7 +244,7 @@ in
       #kibana = 211;# dynamically allocated as of 2021-09-03
       xtreemfs = 212;
       calibre-server = 213;
-      heapster = 214;
+      #heapster = 214; #dynamically allocated as of 2021-09-17
       bepasty = 215;
       # pumpio = 216; # unused, removed 2018-02-24
       nm-openvpn = 217;

nixos/modules/services/monitoring/heapster.nix

@@ -50,8 +50,10 @@ in {
     };
 
     users.users.heapster = {
-      uid = config.ids.uids.heapster;
+      isSystemUser = true;
+      group = "heapster";
       description = "Heapster user";
     };
+    users.groups.heapster = {};
   };
 }