HLTtau DQM: Fixed histogram paths for DQM Displays
Histograms under HLT/TRTAU/Expert/{L1, RNN, basicVars} where not properly linked.
Changed the han file and the histograms can be accessed again from the webdisplay:
https://atlasdqm.cern.ch/webdisplay/test/4/express_express/run_472604