Provision PostgreSQL cluster

Summary:
Database cluster naming convention:

db-<series>-<counter>

Cluster A will be PostgreSQL main, first is db-A-001.
It will host fantoir database.

Ref T1750.

Test Plan: Connect to db-A-001.nasqueron.drake

Reviewers: dereckson

Maniphest Tasks: T1750

Differential Revision: https://devcentral.nasqueron.org/D2760