An application that calls fork() in a loop and then the forked processes call bson_oid_init() will end up with the same oid if called within the same second because the implementation of bson_oid_init() uses a cached per-process random even if BSON_CONTEXT_DISABLE_PID_CACHE is set.

Introduced by:
https://github.com/mongodb/mongo-c-driver/commit/8130e791c2a101a38fe5551c253c7b0dda894d3a