GeezerVison

When git_repository_init_ext is given a workdir_path that names the
repository path itself, treat it as if no working directory was given,
so that the repository goes in a ".git" directory inside it.

Also compare the working directory and the repository parent after
normalizing separators and "." and ".." components when deciding
whether the working directory is the natural one. Previously a path
with backslashes on Windows, or one spelled with a trailing ".", was
treated as a separate working directory and init failed or wrote an
unneeded core.worktree.