Add official driver adapter for pgmock

[nahtnam]

Problem

Currently Prisma does not have support for any sort of in-memory postgres database adapter. This makes testing harder and requires an actual postgres instance running for any sort of integration test

Suggested solution

Recentlyhttps://github.com/stackframe-projects/pgmock has popped up.

If Prisma were to build an official adapter for this tool, we could start using it in Jest/Vitest and load it with dummy data for testing

Related request: #23752
Related request: #11129

Alternatives

Option 1: Run a full blown postgres database
Option 2: Run prisma with sqlite when testing (there will be incompatibilities)
Option 3: Support something like pg-mem (https://github.com/oguimbal/pg-mem) (not supported yet)

Additional context

N/A