python3Packages.python-ly: remove myself from maintainer list

While going through my repology feed of package-updates I realized that
I'm still a maintainer of this. Just did an update in e6a9c15
and the package is pretty easy to maintain, but decided to make it clear
that I don't actively maintain this.

pkgs/development/python-modules/python-ly/default.nix

@@ -16,6 +16,6 @@ buildPythonPackage rec {
   meta = with stdenv.lib; {
     description = "Tool and library for manipulating LilyPond files";
     license = licenses.gpl2;
-    maintainers = with maintainers; [ ma27 ];
+    maintainers = with maintainers; [ ];
   };
 }