Version 251.6 of systemd introduced a small change[1] that now checks
whether the fsck command is available in *addition* to the filesystem
specific fsck.$fsname executable.
When bumping systemd to version 251.7 on our side[2], we introduced that
change. This subsequently caused our "fsck" test to fail and it looks
like this was an oversight during the pull request[3] introducing the
bump.
Since the fsck wrapper binary is in util-linux, I decided to address
this by adding util-linux to fsPackages because util-linux is already
part of the closure of any NixOS system so the impact should be pretty
low.
[1]: 73db7d9932
[2]: 844a08cc06
[3]: https://github.com/NixOS/nixpkgs/pull/199618
Signed-off-by: aszlig <aszlig@nix.build>