Fix bootstrap for services

The bootstrap tasks could be started on any node listed in the
site.yml

The issue is that all the tasks must run on the same node, and the
only node that all the tasks can run on is the 'api' node due to
needing to start the bootstrap container which binds in the configs.

delegate_to is required to ensure that the proper node gets the task.

Co-Authored-By: Sam Yaple <sam@yaple.net>
Change-Id: Ica04ab366777a571a92212ac22c482f1881d4ecd
Closes-Bug: #1513598
Related-Bug: #1513439