remove genesis maintainer

genesis has no longer access to github

pkgs/games/assaultcube/default.nix

@@ -65,7 +65,7 @@ stdenv.mkDerivation rec {
   meta = {
     description = "Fast and fun first-person-shooter based on the Cube fps";
     homepage = "https://assault.cubers.net";
-    maintainers = [ maintainers.genesis ];
+    maintainers = [ ];
     platforms = platforms.linux; # should work on darwin with a little effort.
     license = stdenv.lib.licenses.zlib;
   };