Add support for section_path in nav_repos

[oleg-nenashev]

Submitting for initial feedback

Currently, when using nav_repos, there is no possibility to specify a custom destination for the included repository. The slugify() command removes slashes and hence the directory tree. This patch copies the code from repos with a similar behavior.

When using such an approach, a site developer will have to be careful when specifying a path in nav

[github-actions]

Version Number Check

Version has been updated in pyproject.toml.

[jdoiro3]

@oleg-nenashev, I just fixed some CI issues and merged main into your branch. CI should pass now. Let me know when you're ready for my review and thanks for contributing!

[oleg-nenashev]

Hi. Sure, I would be happy to have this feature integrated If you find it feasible.

It still has certain limitations, because one cannot nest repositories just with that due to the parallel checkout. But it works pretty well otherwise in my PoC. For nesting, I think git submodules would be a preferred option anyway.