Fix use of hydrateRoot in DevTools test (#24084)

I noticed while working on a different PR that this test was not
using hydrateRoot correctly. You're meant to pass the initial children
as the second argument.

packages/react-devtools-shared/src/__tests__/inspectedElement-test.js

@@ -2099,7 +2099,7 @@ describe('InspectedElement', () => {
     await utils.actAsync(() => {
       const container = document.createElement('div');
       container.innerHTML = '<div></div>';
-      ReactDOMClient.hydrateRoot(container).render(<Example />);
+      ReactDOMClient.hydrateRoot(container, <Example />);
     }, false);
 
     const inspectedElement = await inspectElementAtIndex(0);