Builtin cheap HA with distributed SQLite implementations

[riuvshyn]

This is duplicate of #2664

These days there are bunch of solid implementations for HA SQLite setups like:

• https://dqlite.io/
• https://rqlite.io/

It would be amazing to be able to use them and avoid running whole database for each cluster which is very painful and expensive. I am pretty sure there are more people who would love to have this option available.

[MarcosDY]

May this WIP PR be of some help for sure #6888

[kfox1111]

I'm strongly recommending this solution: https://github.com/spiffe/spire-ha-agent

I use it myself.

Otherwise, you run into issues, like, how do you get certificates for the db cluster, so you can use spire to manage certificates.