added docker rootless for pardinus

hosts/pardinus/default.nix

···
       extraGroups = [
         "wheel"
         "tss"
+        "docker"
       ];
       hashedPassword = "$6$rounds=4096$048E1JljebjSdlsY$rDwVNrrNj.bG6JPKoe/K3PxPj3P5K3xnlvICk5gEhwGxFMYoH/APNlKDbNHHc/cPP1KbtDd2oYxqWwVxYDAAE1";
       shell = pkgs.nushell;

modules/server.nix

···
       PasswordAuthentication = false;
     };
   };
+
   networking.firewall.allowedTCPPorts = [ 22 ];
+
+  virtualization.docker = {
+    storageDriver = "btrfs";
+    rootless = {
+      enable = true;
+      setSocketVariable = true;
+    };
+  };
 }