Removed duplicated property Extrapolator from TrackHoleSearchTool

Follow up to !61296 (merged). Property is now declared in header InDetTrackHoleSearchTool.h

Fixes the following warnings

INFO       ITkAmbiguityScore.ITkAmbiguity...ITkHoleSearchTool           0 WARNING duplicated property name 'Extrapolator', see https://its.cern.ch/jira/browse/GAUDI-1023
INFO       ITkAmbiguitySolver.ITkAmbiguit...ITkHoleSearchTool           0 WARNING duplicated property name 'Extrapolator', see https://its.cern.ch/jira/browse/GAUDI-1023
INFO       ITkAmbiguityScoreConversionFin...ITkHoleSearchTool           0 WARNING duplicated property name 'Extrapolator', see https://its.cern.ch/jira/browse/GAUDI-1023
INFO       ITkAmbiguitySolverConversionFi...ITkHoleSearchTool           0 WARNING duplicated property name 'Extrapolator', see https://its.cern.ch/jira/browse/GAUDI-1023
INFO       ToolSvc.ITkTrackSummaryTool.IT...ITkHoleSearchTool           0 WARNING duplicated property name 'Extrapolator', see https://its.cern.ch/jira/browse/GAUDI-1023
...
INFO       MuonSegmentMaker.MuonCl...CombinedMuonIDHoleSearch           0 WARNING duplicated property name 'Extrapolator', see https://its.cern.ch/jira/browse/GAUDI-1023
INFO       MuonSegmentMaker_NCB.Mu...CombinedMuonIDHoleSearch           0 WARNING duplicated property name 'Extrapolator', see https://its.cern.ch/jira/browse/GAUDI-1023
INFO       MuonCombinedMuonCandida...CombinedMuonIDHoleSearch           0 WARNING duplicated property name 'Extrapolator', see https://its.cern.ch/jira/browse/GAUDI-1023
INFO       ToolSvc.CombinedMuonTra...CombinedMuonIDHoleSearch           0 WARNING duplicated property name 'Extrapolator', see https://its.cern.ch/jira/browse/GAUDI-1023
INFO       MuonCombinedAlg.MuonCom...CombinedMuonIDHoleSearch           0 WARNING duplicated property name 'Extrapolator', see https://its.cern.ch/jira/browse/GAUDI-1023
INFO       MuonInsideOutRecoAlg.Mu...CombinedMuonIDHoleSearch           0 WARNING duplicated property name 'Extrapolator', see https://its.cern.ch/jira/browse/GAUDI-1023
INFO       MuGirlStauAlg.MuonStauR...CombinedMuonIDHoleSearch           0 WARNING duplicated property name 'Extrapolator', see https://its.cern.ch/jira/browse/GAUDI-1023
INFO       MuonCaloTagAlg.MuonCalo...CombinedMuonIDHoleSearch           0 WARNING duplicated property name 'Extrapolator', see https://its.cern.ch/jira/browse/GAUDI-1023
INFO       MuonCreatorAlg.MuonCrea...CombinedMuonIDHoleSearch           0 WARNING duplicated property name 'Extrapolator', see https://its.cern.ch/jira/browse/GAUDI-1023
INFO       StauCreatorAlg.StauCrea...CombinedMuonIDHoleSearch           0 WARNING duplicated property name 'Extrapolator', see https://its.cern.ch/jira/browse/GAUDI-1023

FYI @jmasik