Postgres support

[artur9010]

Description

I saw a PR on walletd adding postgres support - SiaFoundation/walletd#57
it would be nice to also have it in renterd as some of users may prefer it over mysql/sqlite

Version

v1.0.6

What operating system are you running (e.g. Ubuntu 22.04, macOS, Windows 11)?

Ubuntu 22.04, kubernetes

Anything else?

No response

[ChrisSchinnerl]

We are adding Postgres support in walletd because it doesn't have support for MySQL yet. We are considering adding support for Postgres to renterd as well but it probably won't happen short term.

Depends on #1134