Merge pull request #30107 from danbst/patch-13

declarative containers: improve example config

nixos/modules/virtualisation/containers.nix

···
                   { config, pkgs, ... }:
                   { services.postgresql.enable = true;
                     services.postgresql.package = pkgs.postgresql96;
+                    
+                    system.stateVersion = "17.03";
                   };
               };
           }