forgejo: update renamed disable registration

profiles/forgejo.nix

@@ -16,7 +16,6 @@ in {
       type = "postgres"; # Database type
       passwordFile = config.age.secrets.forgejo.path;
     };
-    disableRegistration = true;
     domain = "source.jfdic.org"; # Domain name
     rootUrl = "https://source.jfdic.org/"; # Root web URL
     httpPort = 3002; # Provided unique port
@@ -27,6 +26,7 @@ in {
           docutils # Provides rendering of ReStructured Text files
           pygments # Provides syntax highlighting
         ]);
+      service.DISABLE_REGISTRATION = true;
     in {
       mailer = {
         ENABLED = true;