Yes. You will simply need to change the symlink you created while following that tutorial and replace it with an updated one.

unlink /var/www
mkdir /var/www
ln -s /etc/mediawiki /var/www/html

The first line should remove the symlink.
The second line will make the /var/www directory (that was previously a symlink)
The third line will create a new symlink using the /var/www/html location instead of the outdated /var/www one.