fix: various mssql compat fixes (#5483)
[ORM-1056](https://linear.app/prisma-company/issue/ORM-1056/enable-and-fix-tests-for-mssql-engine)
Starts running tests against MSSQL with the query compiler.
I've had to refactor some code to utilize `RowSink`, because there were
many edge case plans with missing `unique` nodes that were causing
problems.