nixos/profiles/minimal: remove redundant lessopen default

Starting in 25.05 `programs.less.lessopen.default = null` so no need
to set this in the profile:

https://github.com/NixOS/nixpkgs/pull/316979

Changed files
-2
nixos
modules
profiles
-2
nixos/modules/profiles/minimal.nix
···
};
programs = {
-
# The lessopen package pulls in Perl.
-
less.lessopen = mkDefault null;
command-not-found.enable = mkDefault false;
fish.generateCompletions = mkDefault false;
};