message: fix: unify how observables are consumed within GraphiQL
  Closes
diff: @@ -1707,16 +1707,16 @@ type Observable<T> = {
  // Duck-type Observable.take(1).toPromise()
  function observableToPromise<T>(observable: Observable<T>): Promise<T> {
  return new Promise((resolve, reject) => {
  - const subscription = observable.subscribe(
  - v => {
  + const subscription = observable.subscribe({
  + next: v => {
  resolve(v);
  subscription.unsubscribe();
  },
  - reject,
  - () => {
  + error: reject,
  + complete: () => {
  reject(new Error('no value resolved'));
  },
  - );
  + });
  });
  }
  