Blender Git Loki

Fix T71596: Bug in io_utils api breaking only on windows.

Stupid mistake, 'original' filepath is a blender-flavored one, with
potentially weird things like the '//' relative 'header'... This can
work on linux (also it could have broken in other places too), but on
windows that is fully invalid path and python `os.path` library just
generates empty result here.

Simply using proper valid path instead fixes it...