The EVG project for the CXX Driver currently use the ID cxx-driver. This repeatedly causes confusion due to inconsistency with the C Driver EVG Project ID: mongo-c-driver. Many other Drivers also use mongo-<lang>-driver.

Rename the EVG project IDs to use mongo-cxx-driver instead of cxx-driver for consistency.

Note: this will break old external links to the EVG projects (e.g. https://spruce.mongodb.com/commits/cxx-driver will now be https://spruce.mongodb.com/commits/mongo-cxx-driver) and likely also break local EVG CLI configurations. Fixing these issues should (hopefully) be trivial.