fix bug where 2 buttons shown on second learn step (#864)
fix bug where 2 buttons shown on second learn step (#864)

jakesyl/ruby-card,eduOS/anki,florianjacob/anki,Stvad/anki,jakesyl/ruby-card,socialpercon/anki-1,holycrepe/anki,weihautin/anki,weihautin/anki,kenjhim/anki,ospalh/libanki3,Arthaey/anki,subfusc/anki,go38/anki,abeyer/anki,hssm/anki,hssm/anki,sunclx/anki,xuewenfei/anki,jkitching/anki,LucasCabello/anki