Fix usage of PrAddUTHitsTool in explicitly UT-less tracking sequence
When calling get_fast_hlt2_tracks_without_UT
without globally disabling the PrAddUTHitsTool
separately the tool will still run which is unexpected as the function already reads "without UT". This is fixed by explicitly setting a flag disabling the tool.
See also gaudi/Gaudi#214
Thanks for reporting @peilian :)