Add tests for mongodb binary `8.x`

Mongodb (server) version `8.0.0` has been released, it should also be added to be tested here.

[Mongodb 8.0.0 blog post](https://www.mongodb.com/blog/post/top-4-reasons-to-use-mongodb-8-0)

[mongoose already showing MMS works with mongodb 8.0.0](https://github.com/Automattic/mongoose/pull/14937)

This is basically a reminder issue for myself.