diy2 - Upgrade small_vector from chobo to itlib

The old small_vector.hpp is not c++20 compliant.

Chobolabs repo is archived, and the code is now maintained by iboB old: https://github.com/Chobolabs/chobo-shl new: https://github.com/iboB/itlib/

I understand this patch is supposed to be treated differently due to 3rd party lib, but not sure how.