dillon1000/react

Check for Suspense boundary in a root Container (#16673)

If we find a Container that might mean that we're on a node that is inside
a Suspense boundary that is directly inside the Container root.

Imagine the div is a Container and the span is a dehydrated instance:

```
<div>
  <!--$-->
  <span />
  <!--/$-->
</div>
```

There's no way to tests this yet since I'm not actually utilizing
the return value yet.

The solution is to just use the same path to check for a Suspense boundary
as if we find a parent instance.