Convenience function, moves all code converting from a PathInfo struct
to to go-nix's NarInfo.
Change-Id: Idf0dcc38675674563f2dfd3286a4a55fa2a24a82
Reviewed-on: https://cl.tvl.fyi/c/depot/+/9593
Autosubmit: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
Reviewed-by: Brian McGee <brian@bmcgee.ie>