This is a fixup to: https://pagure.io/zuul-distro-jobs/pull-request/159

Apparently one thing that was missing is that the set_fact must have cacheable set. I have checked with upstream tox test and they are using that for tox_executable when read here

I was advised to make sure that we are running it in the same host

Cristian Le: before I forget, also make sure you're running it on the same hosts in both plays. On our side I did a check and successfully persisted a variable from one pre playbook into a run playbook (did not check any post, but I'm reasonably sure it would work). I got tripped up when I forgot that localhost is not in all

It should be fine for us though right because zuul would be providing only one host? At least the upstream test also use hosts: all there.

@fab if you can do another quick review