Fix client-side hydration of SSR in React 18

Summary:
See context in ENG-2504.

One serious issue remains here: the PersistGate makes initial client-side render not match SSR, which results in double-rendering the page on web. Not sure why this wasn't an issue before. It unfortunately affects prod just like dev, so this diff on its own won't fix things.

Test Plan: Render web and landing in both prod and dev

Reviewers: atul

Reviewed By: atul

Subscribers: tomek

Differential Revision: https://phab.comm.dev/D5963