Fix lint for IntervalValue example

Author: OBe95

playground/index.tsx

@@ -14,7 +14,7 @@ const mockBackendRequest = (event$: Observable<React.MouseEvent<HTMLHeadElement>
 
 function IntervalValue(props: { interval: number }) {
   const [clickCallback, value] = useEventCallback(mockBackendRequest, 0, [])
-  const intervalValue = useObservable(
+  const intervalValue = useObservable<number, number[]>(
     (inputs$, _) =>
       inputs$.pipe(
         switchMap(([intervalTime]) => interval(intervalTime)),