as this isn't used by consumers, they should be able to remove this
input via `inputs.nixvim.inputs.git-hooks.follows = ""`. it is
especially important here as `git-hooks` has a large amount of inputs
itself
treefmt isn't actually using flake-root to find the flake's root; it
does it itself.
All we were doing was passing flake-root's default `projectRootFile` to
treefmt, which is `"flake.nix"`;
