This patch adds the `profile_tasks` callback plugin to the whitelist
so that we can identify the tasks which are taking the longest amount
of time to run.
setenv=
ANSIBLE_SSH_ARGS = -F {changedir}/vagrant_ssh_config
ANSIBLE_ACTION_PLUGINS = {toxinidir}/plugins/actions
+ ANSIBLE_CALLBACK_WHITELIST = profile_tasks
# only available for ansible >= 2.2
ANSIBLE_STDOUT_CALLBACK = debug
docker_cluster: PLAYBOOK = site-docker.yml.sample