treewide: remove the-kenny from maintainers

@the-kenny did a good job in the past and is set as maintainer in many package,
however since 2017-2018 he stopped contributing. To create less confusion
in pull requests when people try to request his feedback, I removed him as
maintainer from all packages.

pkgs/development/interpreters/scheme48/default.nix

@@ -6,7 +6,6 @@ stdenv.mkDerivation {
   meta = {
     homepage = "http://s48.org/";
     description = "Scheme 48";
-    maintainers = with stdenv.lib.maintainers; [ the-kenny ];
     platforms = with stdenv.lib.platforms; unix;
     license = stdenv.lib.licenses.bsd3;
   };