SearchEngine and scoreThreshold should be optional fileds for QnAMakerOptions

[anastasiia-zolochevska]

As a workaround we had to cast QnAMakerOptions to type any
const qna = new QnAMaker({
knowledgeBaseId: ‘x',
subscriptionKey: ‘x',
top: 4,
} as any);

[Stevenic]

Good feedback.... I'll make those changes. I'd fixed some issues around that but must have missed QnA maker.

[cleemullins]

Please be sure to file tracking bugs against the C# version of the QnA Maker stack.
@johnataylor was in there last and would be a good assignee for them.

[Stevenic]

QnA maker has since be re-written and no longer references search engine