Describe the bug

When using lib.fileset.gitTracked in combination with --store, the build fails with lib.fileset.gitTracked: Expected the argument (/tmp/nix-store/nix/store/8a5a320f0h66jh066qabxkm67msvbcql-source) to point to a local working tree of a Git repository, but it's not.

Steps To Reproduce

1. Create a new git repository

2. Add the following flake.nix

   {
     inputs = {
       nixpkgs.url = "github:NixOS/nixpkgs/release-23.11";
     };
   
     outputs = {nixpkgs, ...}: {
       packages.x86_64-linux.default = let
         pkgs = nixpkgs.legacyPackages.x86_64-linux;
         fs = pkgs.lib.fileset;
       in
         pkgs.stdenvNoCC.mkDerivation {
           name = "gitTrackedBug";
   
           src = fs.toSource {
             root = ./.;
             fileset = fs.gitTracked ./.;
           };
   
           buildPhase = "touch $out";
         };
     };
   }

3. Build with nix build (works as expected)

4. Build with nix build --store /tmp/nix-store/ (this fails)

Additional context

I'm pretty sure this is the same underlying issue as #269283. I think the issue is that the hasStorePathPrefix check fails when it should trigger in the chroot-ed nix store

hasStorePathPrefix has a note about usage with other filesystem roots, which seems relevant

but I don't know enough about how the actual --store implemention works under the hood to comment further.

Notify maintainers

@infinisil

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