Building `statix` requires IFD

[NobbZ]

I have disabled IFD system wide via /etc/nix/nix.conf as that usually warns me about potential problems early.

Today I realised that this breaks building of statix from the flake:

$ nix build github:nerdypepper/statix/09a3a91b80fe231314b241dd414ca552d33103bc
error: cannot build '/nix/store/gniv04iahm9rgfgqj8x9w1wprj6d732p-channel-rust-nightly.toml.drv' during evaluation because the option 'allow-import-from-derivation' is disabled
(use '--show-trace' to show detailed location information)

(Had to use non-HEAD commit to reproduce as I already used --option allow-import-from-derivation true on master to get it work temporarily)