nix-index cache is now updated by flake

apply.sh

@@ -10,13 +10,3 @@ nix build .#yorick-home --no-link
 nix run .#update-home
 nixos-rebuild switch --flake .# --target-host root@localhost
 rm -f result
-set +x
-echo "Updating nix-index cache"
-(
-  filename="index-x86_64-$(uname | tr A-Z a-z)"
-  mkdir -p ~/.cache/nix-index
-  cd ~/.cache/nix-index
-  # -N will only download a new version if there is an update.
-  wget -q -N https://github.com/Mic92/nix-index-database/releases/latest/download/$filename
-  ln -f $filename files
-)