[BUG] the `\` to join asset_folder and img.png can't be resolve by some editor(like Obsidian)

[ACupofAir]

https://github.com/TobinPalmer/pastify.nvim/blob/4a1d1e03c3ae725ee4af796deca8c7c169ef626e/python3/pastify/main.py#L111

may be better to change it to '/'.join([path1, path2]), for the reason that \ is not supported on some case.(I found that Obsidian on windows doesn't support image path conneted by \ using relative path)