> This PR converts our Boost usage to header only. We switch from using our last remaining Boost lib (unit test), to using it's header-only implementation (see https://www.boost.org/doc/libs/1_78_0/libs/test/doc/html/boost_test/adv_scenarios/single_header_customizations/multiple_translation_units.html).
This is a backport of core#24301
Depends on D13990