packaging/components.nix: Don't import a symlink (backport #12450)

[mergify]

Motivation

This is a workaround to avoid differing evaluation results between Nix 2.19 and >= 2.20 (#12449).

Context

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The Nix maintainer team uses a GitHub project board to schedule and track reviews.

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This is an automatic backport of pull request #12450 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of 2e20a5f has failed:

On branch mergify/bp/2.24-maintenance/pr-12450
Your branch is up to date with 'origin/2.24-maintenance'.

You are currently cherry-picking commit 2e20a5f82.
  (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)

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   packaging/components.nix

no changes added to commit (use "git add" and/or "git commit -a")

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

[edolstra]

Closing, not applicable.