contint: remove ruby-bundler outdated package

The ruby bundler shipped by Ubuntu Precise is way too old and we do not
use it.  One can either use the version provided in
integration/jenkins.git or install the gem version.

Bug: 58040
Change-Id: Ica53d458fe11b4c0cde7ea7d6b949b2e3fd73ea9
Merge "contint: remove ruby-bundler outdated package" into production