Repro case with a master build: https://codesandbox.io/s/stoic-mcnulty-dhygf?file=/src/App.js:668-703

Expected: we see content after a second.
Actual: fallback never resolves.

This happens in a sequence of:

1. Normal update
   - which suspends
2. Idle update
   - which also suspends
3. An unrelated normal update immediately followed by a ping (so they're batched)
   - here, we decide to stay on fallback, but should've shown the content

If you remove `_setVersion(v => v + 1);` on line 44 then the issue goes away.
expect(Scheduler).toFlushAndYield(['B']);
      expect(ReactNoop.getChildren()).toEqual([span('B')]);
    });
  });
  
  it('disables suspense config when nothing is passed to withSuspenseConfig', async () => {
    function App({page}) {
      return (
        <Suspense fallback={<Text text="Loading..." />}>
          <AsyncText text={page} ms={2000} />
        </Suspense>
      );
    }
    
    ReactNoop.render(<App page="A" />);
    expect(Scheduler).toFlushAndYield(['Suspend! [A]', 'Loading...']);
    Scheduler.unstable_advanceTime(2000);
    await advanceTimers(2000);
    expect(Scheduler).toHaveYielded(['Promise resolved [A]']);
    expect(Scheduler).toFlushAndYield(['A']);
    expect(ReactNoop.getChildren()).toEqual([span('A')]);
    
    React.unstable_withSuspenseConfig(
      () => {
        
        
        React.unstable_withSuspenseConfig(() =>
          ReactNoop.render(<App page="B" />),
        );
      },