feat: allow for Postgres password secret generation

[Racer159]

Description

This allows for the Postgres password secret to be generated in the config chart directly

Related Issue

Fixes #145

Type of change

• [ ] Bug fix (non-breaking change which fixes an issue)
• [X] New feature (non-breaking change which adds functionality)
• [ ] Other (security config, docs update, etc)

Checklist before merging

• [X] Test, docs, adr added or updated as needed
• [X] Contributor Guide Steps followed

[Racer159]

Wasn't sure the best way to test but we will pick this up in the next uds-prod deployment - I did mess with it locally though:

No password:

Password: