tauRecTools and METUtilities: update MVA TES parametrisation
This MR is a follow-up of !48327 (merged) , this time for 21.2. A new function is implemented in the CombinedP4FromRecoTaus tool to provide tau MVA energy resolution for the MET significance calculation. So far, only the calo-only energy resolution was provided for analysis usage, but the calo-only Tau Energy Scale calibration is long superseded by the MVA TES calibration. The old method has been kept for compatibility reasons, but a WARNING is issued in case people attempt to use it.
The MVA energy resolution has been derived by @cleitgeb in ATLTAU-1683. The new calibration file (renamed "combinedTES_FinalCalib.root") is now on EOS, soon on cvmfs. For completeness I have updated the file being used by CommonSmearingTool in TauAnalysisTools, but it shouldn't change anything.
Compared to the old method which was returning an absolute energy resolution, the new method provides a relative energy resolution, because this is what is used for MET significance calculation.
There is also a WARNING in case the parametrisation is not applicable (out-of-range in eta, unexpected PanTau decay mode). I put WARNING to maximise the chance that this won't be unnoticed if analyses get many such "invalid taus", in which case we'll have to adapt the parametrisation (currently a dummy 100% resolution is returned for invalid taus).
Cleanup was done on a best effort basis, but that could be further improved.