mmv-go: remove maintainer

pkgs/tools/misc/mmv-go/default.nix

···
     homepage = "https://github.com/itchyny/mmv";
     description = "Rename multiple files using your $EDITOR";
     license = licenses.mit;
-    maintainers = with maintainers; [ zowoq ];
+    maintainers = with maintainers; [ ];
     mainProgram = "mmv";
   };
 }