nixos/fonts: remove fontconfig-penultimate

[flokli]

Motivation for this change

fontconfig-penultimate was a minimalistic fork of the abandoned fontconfig-ultimate. It also hasn't received any updates in the last 3 years. With fontconfig being in much better shape these days, there's no need to keep it.

#92571 (comment)

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.

[flokli]

@ttuegel any opinions?

[infinisil]

Sounds very reasonable :)

[worldofpeace]

Yep, I was planning to do this after we already removed fontconfig-ultimate. But I think we should add a mention in the release notes for 20.09.

[infinisil]

In this case I don't think we need a release notes entry, because an explanatory error is already being thrown if people used it before. Imo release notes are only necessary for things we can't have nice warnings/errors for.