Remove non-lmdb stores from unit tests

[G-D-Petrov]

Reference Issues/PRs

Fixes #1564

What does this implement or fix?

It remove all simulators from the unit tests (e.g. S3 moto, azurite, mongo)

TODO - make sure that we don't need these tests, if we don - add them to the integration tests

[G-D-Petrov]

Moved the test_fork test to integration as it seems sensible to test this with a s3 simulation at least With these changes, locally the unit tests run in ~2min in comperisson to ~7min before them with ARCTICDB_FAST_TEST_ONLY=1 @alexowens90 - do we need to test the QB aggregations with s3/azure simulations or is lmdb enough?

[willdealtry]

Are we sure this is a good idea? Azurite and Mongo are quite irritating in that they mostly fail locally, but S3 is the storage that the vast majority of our users actually use. This means we're removing more than half the tests in the whole project from the one storage that actually matters to the majority of people, which seems like a high price to pay for knocking a few minutes off a CI run