To uninstall unity-scope-yelp just follow these instructions.
sudo apt-get remove unity-scope-yelp
This will remove just the unity-scope-yelp package itself.
sudo apt-get remove --auto-remove unity-scope-yelp
This will remove the unity-scope-yelp package and any other dependant packages which are no longer needed.
If you also want to delete your local/config files for unity-scope-yelp then this will work.
sudo apt-get purge unity-scope-yelp
Or similarly, like this unity-scope-yelp
sudo apt-get purge --auto-remove unity-scope-yelp
|Maintainer||Ubuntu Developers <firstname.lastname@example.org>|
|Description||Help scope for Unity|