Fix NPE in Interactive.tsx
Fix NPE in Interactive.tsx

Summary: Fixed some incorrect non-null assertions that showed up in monitoring.

Reviewed By: timur-valiev

Differential Revision: D32278433

fbshipit-source-id: afe4913d8aef38c371461b4d0b817b2625153de1

facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper