Motivation for this change

nix-env -f "<nixpkgs>" -qaP -A emacsPackagesNg.melpaPackages
nix-env -f "<nixpkgs>" -qaP -A emacsPackagesNg.melpaStablePackages

fail with error: attribute 'XXXXX' missing, at /nix/nixpkgs/pkgs/applications/editors/emacs-modes/melpa-packages.nix:XXX:XX messages as super doesn't contain the referenced attributes anymore.

Things done

Remove obsolete packages.

• Tested using sandboxing (nix.useSandbox on NixOS, or option build-use-sandbox in nix.conf on non-NixOS)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s):
  • nixos/tests/emacs-daemon.nix
• Tested compilation of all pkgs that depend on this change using nix-shell -p nox --run "nox-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Fits CONTRIBUTING.md.