Feature request: in-memory variant of Doltgres (disposable instances for unit testing apps)

Hi!

Would you consider offering an "in-memory" (RAM storage / backend) variant of Doltgres, for fast, disposable databases in unit testing of apps? I am not sure if that's technically possible, but it would be very nice to have if it is.

- Postgres itself *doesn't* support that (it's very tied to the filesystem I think) but it could be a great selling point for Doltgres
- The closest I found is [pg-mem](https://www.npmjs.com/package/pg-mem), which works well for simple tests, but it's only an emulation
- I think MySQL has a [MEMORY Storage Engine](https://dev.mysql.com/doc/refman/8.4/en/memory-storage-engine.html) which is probably roughly what I mean (I have no experience with that, it seems to have limitations)

This is more of a "nice-to-have" for me, but I would be very interested to learn your thoughts on this, and whether it could be considered in the roadmap.