Fix windows build (backport #12794)

[mergify]

Motivation

PR #12767 accidentally broke it.

Context

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This is an automatic backport of pull request #12794 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of 99041b4 has failed:

On branch mergify/bp/2.24-maintenance/pr-12794
Your branch is up to date with 'origin/2.24-maintenance'.

You are currently cherry-picking commit 99041b4d8.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   src/libstore/local-store.cc
	modified:   src/libutil/file-system.cc

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   src/libutil/file-system.hh

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally