Extract variable for React root

extensions/ql-vscode/src/view/webview.tsx

@@ -26,7 +26,8 @@ const render = () => {
   // eslint-disable-next-line @typescript-eslint/no-var-requires
   const view: WebviewDefinition = require(`./${viewName}/index.tsx`).default;
 
-  createRoot(element).render(
+  const root = createRoot(element);
+  root.render(
     // Post a message to the extension when fully loaded. See https://github.com/reactwg/react-18/discussions/5 ("What about the render callback?")
     <div ref={() => vscode.postMessage({ t: "viewLoaded", viewName })}>
       {view.component}