fix ATLASRECTS-5098 irreproducibility issue, using vector of pair instead of...
partly fix ATLASRECTS-5098 irreproducibility issue, using vector of pair instead of multimap to keep track and its score.
ATLASRECTS-5098 reports irreproducibility issues on TrackCollection and PixelGangedClusterAmbiguities leaves in ESD root file.
This MR fix irreproducibility issue on TrackCollection.
PixelGangedClusterAmbiguities irreproducibility issue is still under investigating.
Edited by Yi Liu