Add a job which runs testinfra for the eavesdrop server. When we
have a per-hostgroup playbook, we will add it to this job too.
The puppet group is removed from the run-base job because the
groups.yaml file is now used to construct groups (as it does
in production) and will construct the group correctly.
The testinfra iptables module may throw an error if it's run
multiple times simultaneously on the same host. To avoid this,
stop using parallel execution.
Change-Id: I1a7bab5c14b0da22393ab568000d0921c28675aa