treewide: remove worldofpeace from meta.maintainers

(It was requested by them.)
I left one case due to fetching from their personal repo:
pkgs/desktops/pantheon/desktop/extra-elementary-contracts/default.nix

pkgs/development/libraries/libunity/default.nix

@@ -65,6 +65,6 @@ stdenv.mkDerivation {
     homepage = "https://launchpad.net/libunity";
     license = licenses.lgpl3;
     platforms = platforms.linux;
-    maintainers = with maintainers; [ worldofpeace ];
+    maintainers = with maintainers; [ ];
   };
 }