hswaw/machines/customs: upgrade to workspace nixos-unstable 2021-08-11

Change-Id: I6eb4408d40e14f24ebbe3f9f3aef0be952b44e8b
Reviewed-on: https://gerrit.hackerspace.pl/c/hscloud/+/1167
Reviewed-by: vuko <vuko@hackerspace.pl>
diff --git a/hswaw/machines/customs.hackerspace.pl/mikrotik-exporter.nix b/hswaw/machines/customs.hackerspace.pl/mikrotik-exporter.nix
index 26399f3..8ea056e 100644
--- a/hswaw/machines/customs.hackerspace.pl/mikrotik-exporter.nix
+++ b/hswaw/machines/customs.hackerspace.pl/mikrotik-exporter.nix
@@ -18,7 +18,8 @@
 in {
   users.users."${user}" = {
     group           = "${group}";
-    useDefaultShell = true;
+    isSystemUser = true;
+    uid = 1003;
   };
   users.groups."${group}" = {};