Sandbox: https://codesandbox.io/s/cranky-kapitsa-op3jh

Repro: type "a" and then after a second "b"

Expected: Eventually you'll see "ab" in all fields. Pending "..." indicator goes away.

Actual: You'll keep seeing "a" in low pri field. Pending "..." indicator is stuck.
const [counter, setCounter] = useState(0);
        const [signal, setSignal] = useState(true);
        
        if (signal !== newSignal) {
          setCounter(c => c + 1);
          setSignal(newSignal);
          if (counter === 0) {
            
            
            Scheduler.unstable_yieldValue('Suspend!');
            throw thenable;
          }
        }
        return <Text text={counter} />;
      }
      const root = ReactNoop.createRoot();
      root.render(<Foo signal={true} />);
      expect(Scheduler).toFlushAndYield([0]);
      expect(root).toMatchRenderedOutput(<span prop={0} />);
      root.render(<Foo signal={false} />);
      expect(Scheduler).toFlushAndYield(['Suspend!']);
      expect(root).toMatchRenderedOutput(<span prop={0} />);
      
      root.render(<Foo signal={false} />);
      expect(Scheduler).toFlushAndYield(['Suspend!']);
    });
    it('discards render phase updates if something suspends, but not other updates in the same component', async () => {
      const thenable = {then() {}};