FIX: Remove category id from category class name (PR #10712)

The generated class name included ID (parent_slug-child_slug-child_id), but the client side did not expect it (parent_slug-child_slug).

GitHub

What not use category.slug_path?

Does it work with sub-sub-categories?

I wanted at first, but slug_path is not cached, but full_slug is (because url is).

Yes, it works with sub-sub-categories. :blush: