We should adopt a hybrid approach for generating Bucket OIDs by using a full 8-byte counter and only randomizing those bytes when we hit OID collisions. This should still reap the benefits of
SERVER-78080 and address PERF-4352.
Context: as a result of
SERVER-78080 (fully randomizing the last 8 bytes of bucket OID values), we saw a significant regression detailed in PERF-4352.