FIX: import correctly rainfdates parameter

app/otbTimeSeriesIndexTrend.cxx

@@ -382,7 +382,7 @@ private:
       {
 
         // Get the rainfall time series dates
-        std::vector<DateType> rainDates = GetTimeSeriesDates("rainfdates");
+        std::vector<DateType> rainDates = GetTimeSeriesDates(GetParameterAsString("rainfdates"));
 
         // Get the rainfall time series input images list
         FloatVectorImageListType::Pointer inRFList = this->GetParameterImageList("rainfts");