test: run database tests in CI

[momentiris]

• Adds mssql service to gh action test suite and connect to it when testing.
• adds a withContext test helper that wraps each test in a db transaction and rollbacks after test finish
• rewrites all tests that use db to use withContext
• side effect: start adding db as param to adapter functions instead of them referencing the export themselves.

At first I thought running in transactions like this would allow us to parallelize tests but unfortunately not.. yet.
Something about how mssql works with transactions which I don't understand yet.

Todo:
Investigate what this does and if it's problematic to use in test and not in prod.

ALTER DATABASE [tenants-leases-test] SET READ_COMMITTED_SNAPSHOT ON;

It allows us to run multiple jest workers for the db tests that now run in transactions.

• https://learn.microsoft.com/en-us/dotnet/framework/data/adonet/sql/snapshot-isolation-in-sql-server
• https://stackoverflow.com/questions/74405636/ms-sql-postgresql-behavior-against-read-committed-isolation-level-is-acting-di

[driatic]

Nothing to remark on, looks great!