nixos/tcsd: make group uid dynamic

nixos/modules/misc/ids.nix

@@ -210,7 +210,7 @@ in
       #fleet = 173; # unused
       #input = 174; # unused
       sddm = 175;
-      tss = 176;
+      #tss = 176; # dynamically allocated as of 2021-09-17
       #memcached = 177; removed 2018-01-03
       #ntp = 179; # dynamically allocated as of 2021-09-17
       zabbix = 180;

nixos/modules/services/hardware/tcsd.nix

@@ -149,12 +149,10 @@ in
     users.users = optionalAttrs (cfg.user == "tss") {
       tss = {
         group = "tss";
-        uid = config.ids.uids.tss;
+        isSystemUser = true;
       };
     };
 
-    users.groups = optionalAttrs (cfg.group == "tss") {
-      tss.gid = config.ids.gids.tss;
-    };
+    users.groups = optionalAttrs (cfg.group == "tss") { tss = {}; };
   };
 }