openWakeword should detect a non-working wakeword page

[ianb]

In main.js:openWakeword there's code that finds a wakeword tab and sends a message:

    await sendMessage({ type: "updateWakeword" }, { tabId: tabs[0].id });

But it doesn't catch any errors, so if the page is open but not working then it won't reload. It should catch an error and reload.