Use edm::SerialTaskQueue for syncrhonization for on-demand SiPixelClusterShapeCache
SQ: Move SiPixelClusterShapeCache to SiPixelCluster
SQ: SiPixelClusterShapeCacheProducer
SQ: ClusterShapeSeedComparitor
SQ: ClusterShapeHitFilter and ClusterShapeHitExtractor
SQ: LowPtClusterShapeSeedComparitor
SQ: ClusterShapeTrackFilter, ClusterShapeTrajectoryFilter, and PixelTripletLowPtGenerator