🐛 Issue with partial and variable names

[mhesselbarth]

I ran into this strange bug for the gdb engine and calculating partial response function. If two variables have a name overlap, for example, dbh and dbh_cv, there is an issue with variable selection. Instead of only one column for the current v, two columns get returned, namely the current v but also the one with a name overlap.

mboost::predict.mboost(object = self$get_data('fit_best'),
                                                      newdata = dummy_temp, which = v,
                                                      type = type, aggregate = 'sum') 

A hacky solution is to use which = which(names(dummy_temp) == v) instead of which = v. This returns an integer with the column id of the current v