Add missing features in unified test format (#820)

* CDRIVER-4066 "Support" version 1.2 of unified test format

Since the only tests that are using the loop operation and storeEventsAsEntities are the drivers-atlas-testing tests, we can defer implementation of those two features until the atlas testing project.

* CDRIVER-4060 Implement version 1.3 of unified test format

Note that implementing the serverless topology check will be done separately

* CDRIVER-4064 Support serverless runOnRequirement in test runner

* Avoid early exit in complex check functions

Co-authored-by: Kevin Albertson <kevin.albertson@10gen.com>

* Error when encountering unsupported functionality

* Don't call result_check when ignoreResultAndError is used

* Reference CMAP ticket

* Don't require saveResultAsEntity for createFindCursor operation

* Set return value after fetching data from cursor

Co-authored-by: Kevin Albertson <kevin.albertson@10gen.com>