OstapHEP/ostap: v1.9.4.0

v1.9.4.0 New features: Add Ostap::Math::FlatteBugg , Ostap::Models::FlatteBugg and FlatteBugg_pdf add addition for two `ROOT.RooPlot~ objects with the same structure more tuning for Ostap::Utils::FitResult add ROOT.TTree.fstatVar and ROOT.TTree.fstatVars methods extend test_tools_tmva.py to include all 5 ways to use TMVA results add counters_table fnuction to printing the counters as a table fix/impove issue with standard TMVA plots update TMVA examples/tests add full_path mehtods for ROOT.TDirectory and ROOT.TTree improve addTMVAresponce functons rmeove comma separator sfrom ds_project slightly improve the prints from tree_reduce Backward incompatible: Bug fixes: fix formfactor for Ostap::Math::ChannelFlatteBug