Fix scifi states access for BestTrackCreator
The way of accessing scifi states for lepton_id computation was problematic for the long tracks originating from the seeding & matching algorithm, in case the best_track_creator was used. This MR aligns the long track scifi states between Forward and Seeding & matching tracks and ensures that they are accessed correctly when running either individual or combined track sequences.
Closes #428 (closed)