enable defaultValue to be an async function

[sibelius]

Version

• i18next: 11.10.2
• i18next-scanner: 2.10.1

I'd like to let my defaultValue return an async function like this:

defaultValue: async (lng, ns, key) {
      if (lng === 'en') {
        // Return key as the default value for English language
        return key;
      }

      const translated = await getTranslatedValueForKey(key, lng);

     return translated;
 },