fix(playwright): Add missing await on page.evaluate

[KuSh]

Hi,

This missing await causes us many, hard to debug problems, when page has been closed prematurely (popup or terminating analysis if too long)

Simple reproduction :

(async () => {
  const browser = await playwright.chromium.launch({ headless: true });
  const context = await browser.newContext();
  const page = await context.newPage();
  await page.close();
  try {
    const results = await new AxeBuilder({ page }).analyze();
    console.log(results);
  } catch (error) {
    console.error(error);
  }
  await browser.close();
})();
// node:internal/process/promises:279
            triggerUncaughtException(err, true /* fromPromise */);
            ^
 page.evaluate: Target page, context or browser has been closed

I haven't been able to write a simple test that reproduce the problem but I can reproduce it in my project and adding that await fixed all my problems

No QA needed

[CLAassistant]

All committers have signed the CLA.

[straker]

Thanks for the pr! Before we can merge it you'll need to sign our CLA, but it's not working at the moment. Once we get that fixed I'll let you know, then we can work on getting this merged in.

[straker]

Going to close / reopen this pr to retrigger the cla bot, which should be working now.

[straker]

Review for security