`check` command fails on valid path where `fix` succeeds

[nrdxp]

I started using statix in CI and we ran into a very strange error, I reduced it down to this minimal reproduction:

./${f}.f

This is a valid path, and if f is set to say "foo", then nix would eval it successfully to $PWD/foo.f. To make matters a little stranger, if you run statix fix on this same path it exits with a 0 exit status, no error reported. There must be some divergence between the check logic in the check command, and that in the fix command.