Reference docs for driver adapters

[nikolasburk]

We don't have a proper "reference doc" for the driver adapter API (e.g. PrismaPg) but only instructions for using them, e.g. here.

We should add a proper reference that outlines all the options the driver adapters can be instantiated with, similar e.g. to the PrismaClient reference docs.

There are several potential places for this:

• on the DB-specific page under https://www.prisma.io/docs/orm/overview/databases
• on the regular Prisma Client reference page: https://www.prisma.io/docs/orm/reference/prisma-client-reference
• a new page (e.g. called "Driver adapters") under Reference: https://www.prisma.io/docs/orm/reference

Personally, I would vote for the 3rd option but make sure to crosslink from each DB-specific page where relevant.

As part of this work, we need to include this issue: #5722