Set ITkRotCreatorCfg as a private tool instead of public to avoid inconsistencies with multiple tracking passes configuration

When trying to run an Athena reconstruction job and saving seeds for both the main and conversion pass (i.d. by setting flags.Tracking.doStoreTrackSeeds=True;flags.Tracking.ITkConversionPass.storeTrackSeeds=True; in the preExec) I run into problems, with the job complaining about conflicting settings for the SplitClusterAmbiguityMap property.

It turns out this is related to the fact that ITkSeedToTrackConversionTool sets the ITkRotCreator as a public tool, but unfortunately the ITkRotCreator will then set the ITkPixelClusterOnTrackTool assigning to it the SplitClusterAmbiguityMap property (which name changes according to the tracking pass).

This is a quick fix: set different ITkRotCreator with different names according to the tracking pass. @tstreble @ncalace do you have suggestions?