main-cleanup3a-PixelDigitization
Building on earlier MRs, this implements proposals 20-22 of ATLASRECTS-7721:
- delete all calls to getFEI4ChargScaling sic (this scaling factor is always set to 1.0)
- remove "if getUseFEI4SpecialScalingFunction", as this bool is always true
- replace use of PixelModuleData::getFEI4ToTSigma(int tot) with a local function, as this simply returns an element in a vector which is never changed.