Add a new sTGCSimHitCollection_p3 to record extra hit info required by sTGC Digitization

The new sTGCSimHitCollection_p3 persistent representation brings the following changes: migration to HepMcParticleLink_p2, adding the kinetic energy and pre-step position, and removing the direction vector. For some reason, the sTGC still uses HepMcParticleLink_p1 before this merge request, but this change doesn't have major impact on the sTGC digitization. The hit kinetic energy and pre-step position are required by the sTGC digitization to process hits from particles created inside the sTGC chambers and other uncommon tracks. The direction vector is not needed, since it can be derived from the hit pre-step and post-step position.