Remove downloads from ubuntu repo
Remove downloads from ubuntu repo

As nodes should have access to ubuntu repository we don't need to
download ubuntu packages in the pre_build_hook before installing the
plugin.

Change-Id: I4dd2d3a08607048f9e34d998705595ff27b283c0

stackforge/fuel-plugin-lma-collector,stackforge/fuel-plugin-lma-collector,stackforge/fuel-plugin-lma-collector,stackforge/fuel-plugin-lma-collector,stackforge/fuel-plugin-lma-collector