Fix error in non-home paths

[samoylovfp]

Before it would fail in paths outside the home directory with

 × Pipeline empty.
    ╭─[/home/filipp/.config/nushell/panache-git.nu:32:76]
 31 │   let current_dir_relative_to_home = (
 32 │     do --ignore-errors { $current_dir | path relative-to $nu.home-path } | str join
    ·                                                                            ────┬───
    ·                                                                                ╰── no input value was piped in
 33 │   )
    ╰────

[fdncred]

Thanks