message: prevent botkit from erroring when the step results are not a string
diff: @@ -611,7 +611,7 @@ export class BotkitConversation<O extends object = {}> extends Dialog<O> {
  // TODO: Allow functions to be passed in as patterns
  // ie async(test) => Promise<boolean>
  - if (step.result.match(test)) {
  + if (step.result && typeof(step.result) == 'string' && step.result.match(test)) {
  path = condition;
  break;
  }
  