[Fizz] Pass batch as argument to revealCompletedBoundaries (#33330)

Follow up to #33293.

This solves a race condition when boundaries are added to the batch
after the `startViewTransition` call.

This doesn't matter yet but it will once we start assigning names before
the `startViewTransition` call.

A possible alternative solution might be to ensure the names are added
synchronously in the event that adds to the batch. It's possible to keep
adding to a batch until the snapshot has happened.