chore(users): grfn -> aspen

Change-Id: I6c6847fac56f0a9a1a2209792e00a3aec5e672b9
Reviewed-on: https://cl.tvl.fyi/c/depot/+/10809
Autosubmit: aspen <root@gws.fyi>
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
Reviewed-by: lukegb <lukegb@tvl.fyi>

users/aspen/bbbg/arion-compose.nix

@@ -0,0 +1,15 @@
+{ ... }:
+
+{
+  services = {
+    postgres.service = {
+      image = "postgres:12";
+      environment = {
+        POSTGRES_DB = "bbbg";
+        POSTGRES_USER = "bbbg";
+        POSTGRES_PASSWORD = "password";
+      };
+      ports = [ "5432:5432" ];
+    };
+  };
+}