At the moment we test only against the latest server, deployed as a standalone. As we expand the MongoDB configurations we test against, the C++ Driver will have to check how MongoDB is configured and decide which tests to skip and what expectations to assert within tests, the same as other drivers.

Let's follow PyMongo's lead: once when the tests start, call "isMaster" and fill out a struct of information about the deployment, such as its min and max wire versions, whether it is a replica set, the number of nodes, whether test commands are enabled, etc.

"Catch" allows test fixtures with a relevant example:

https://github.com/catchorg/Catch2/blob/master/docs/test-fixtures.md#top