How to include folders from main repo when serving github pages from /docs?

I’m looking to include some markdown files that are in a folder /foo/bar/ from the root of my repo in my GitHub pages Jekyll site. I’ve tried symbolically linking the folder to the right location in /docs/_pages but GitHub gives me the error:

Your site is having problems building: The symbolic link /foo/bar targets a file which does not exist within your site's repository. For more information, see

I understand that as my site is being hosted from /docs in my repository, by linking to /foo/bar, I am linking to a file outside the sites folder but how do I include this folder considering that they are in the same repo?

As I wanted to keep my site in the /docs folder I used GitHub actions to copy the relevant files on every push.