Fix not being able to convert beatmaps with 0 hitobjects
Fix not being able to convert beatmaps with 0 hitobjects

NeoAdonis/osu,DrabWeb/osu,naoey/osu,naoey/osu,EVAST9919/osu,smoogipoo/osu,smoogipoo/osu,ZLima12/osu,2yangk23/osu,NeoAdonis/osu,UselessToucan/osu,naoey/osu,smoogipoo/osu,ZLima12/osu,ppy/osu,UselessToucan/osu,peppy/osu,peppy/osu,UselessToucan/osu,ppy/osu,smoogipooo/osu,DrabWeb/osu,EVAST9919/osu,DrabWeb/osu,NeoAdonis/osu,peppy/osu-new,johnneijzen/osu,peppy/osu,2yangk23/osu,ppy/osu,johnneijzen/osu