[NTG-context] Remove italics from bibliography list

I tried several variants, but I cannot find where exactly the switch happens. \definebtx[apa:list:title:incollection][apa:list:title][style=] \definebtx[apa:list:title:book][apa:list:title][style=] \definebtx[apa:list:journal][apa:list][style=]