To uninstall ruby-omniauth-wordpress just follow these instructions.
sudo apt-get remove ruby-omniauth-wordpress
This will remove just the ruby-omniauth-wordpress package itself.
sudo apt-get remove --auto-remove ruby-omniauth-wordpress
This will remove the ruby-omniauth-wordpress package and any other dependant packages which are no longer needed.
If you also want to delete your local/config files for ruby-omniauth-wordpress then this will work.
sudo apt-get purge ruby-omniauth-wordpress
Or similarly, like this ruby-omniauth-wordpress
sudo apt-get purge --auto-remove ruby-omniauth-wordpress
|Maintainer||Debian Ruby Extras Maintainers <email@example.com>|
|Description||Wordpress strategy for OmniAuth|