Don't write resolv.conf file manually
resolv.conf file is supposed to be written by the NetworkManager. In
kubuntu images symlink to resolvconf generated resolv.conf was missing
due to package not being configured.
So this hack is no longer needed
Reviewers: sebas, graesslin, garg
Reviewed By: graesslin, garg
Differential Revision: https://phabricator.kde.org/D240