Use PyC_ParseUnicodeAsBytesAndSize parser instead of "s" / "z" type specifier. This relates to #111033, resolving Python exceptions which causes icons not to load (for e.g.). Now bytes are also supported as path arguments.
- Remove redundant void, struct. - Use function style casts.
Also see #103343. Pull Request: https://projects.blender.org/blender/blender/pulls/110352