It replaces some
ParameterType_InputVectorData when relevant.
These modifications were delayed in order to wait for QGIS 3.18 release which embed this PR. It indeed needs the support of field selection for MultipleLayers in
TrainImagesClassifier (which is a composite of the other modified applications)
I would like to update QGISInterface.rst but I'm not sure in which OTB version this modification will land (8.0 ? 8.1.0?).