Use sync-vagrant-conf wrapper script to deal with puppet manifest
Instead of using 1. prepare-vagrant-conf then 2. watch-vagrant-conf. Let sync* do everything delegating to each its job.
Related to T3833
Test Plan
Actually use it does the right thing. If the /tmp/puppet is not there, it calls prepare-vagrant-conf first. (otherwise skips it) Then calls the watch-vagrant-conf.
Migrated from D6931 (view on Phabricator)