It’s the same. As far as Linux is concerned everything is a file so the ln command works the same for folders, devices, and files.
So you have your git controlled folder, let’s say it’s /opt/openhab. Then you need to create symbolic links so that /etc/open have points to /opt/openHAB/conf.
I always forget the other of the arguments so look it up to verify but I think it’s:
sudo ln -s /etc/openhab2 /opt/openhab/conf