Default to PostgreSQL 12 in Omnibus for new installs
In 13.6 we will make PG12 the default version for new installs and upgrades.
- For new installs of Omnibus GitLab, PostgreSQL 12 is used by default
- Users can opt to use PostgreSQL 11 during a new install
- Upgrades of existing deployments will stay on PostgreSQL 11 unless the user manually upgrades the PostgreSQL version
Issue used when defaulting to PG 11: #5092 (closed)