nixos/thefuck: move init scripts to programs.*.interactiveShellInit

[Ma27]

Motivation for this change

fuck should only be used for interactive sessions, but nothing more
(so init files like /etc/zshenv become even more lightweight).

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS)
• 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 nox --run "nox-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)
• Fits CONTRIBUTING.md.

---

[Ma27]

checked inside a VM with the following configuration:

{
  test = {
    users.extraUsers.vm = {
      initialPassword = "vm";
      extraGroups = [ "wheel" ];
    };

    programs = {
      fish.enable = true;
      zsh.enable = true;
      thefuck.enable = true;
    };
  };
}