Add flag to always check the count of SP before starting tracking reco

This is related to: https://its.cern.ch/jira/browse/ATLASRECTS-7400 An option is added to TrackFinder that forces to do SP counting before the tracking and to respect the limits set in maxNumberPIXsp and maxNumberSCTsp.

e.g. adding a piece below to postExec allows the LargeD0 tracking to run smoothly for HI PC data: trkf=cfg.getEventAlgo("InDetSiSpTrackFinderLowPtLargeD0");trkf.alwaysProtectAgainstBusyEvents=True; trkf.maxNumberPIXsp=10000;trkf.maxNumberSCTsp=10000;

Tagging @goetz