Fix post deployment migrations in Zero Downtime upgrade to run directly against database

A customer recently had migrations when specifically running the Zero Downtime upgrade playbook specifically against Linux Package (Omnibus) postgres.

Issue suggested that migrations appear to be running through PgBouncer incorrectly and investigation found that Post Deployment migrations specifically will be running through PgBouncer in error due to a missed call to reconfigure to update config correctly to point directly to database.