Add Acts AMVF / Acts primary vertex finder package

This MR adds the Acts primary vertex finder package, for now including an ActsAdaptiveMultiPriVtxFinderTool that does the necessary EDM conversion of tracks to be usable by the Acts vertexing, the call to the Acts AMVF itself and reconversion to xAOD::Vertex objects (including HS vertex selection etc.).

This code does currently not affect any of the Athena primary vertexing code or configuration. Dedicated code as well as an ActsPrimaryVtxFinderAlg already exist, but will be added in a later MR after full validation.

FYI: @ncalace, @asalzbur, @vcairo, @kostyuk, @npetters, @goblirsc