Why boundaries is std::list

[ondra-novak]

opentelemetry-cpp/sdk/include/opentelemetry/sdk/metrics/data/point_data.h

Line 59 in b8b715f

std::list<double> boundaries_ = {};

Just explain me, why list is used here. Unless you need to insert into or erase from inside of the list, this container is very slow and you are loosing a lot of performance here.

This has been changed from std::vector in commit a7e814a without any sign of need such a change and without explanation.

[lalitb]

I can't recall why this was done now, but agree std::vector ( or perhaps std::array) would be more efficient. Creating a issue out of it. Thanks for raising the query.