fix: locale switching middleware in static build

[BobbieGoede]

🔗 Linked issue

• Locale not found when generating using lazy translations #3319
• Cannot change locale in SPA mode #3322

❓ Type of change

• 📖 Documentation (updates to the documentation, readme or JSdoc annotations)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

Resolves #3319
Resolves #3322

This aims to fix regressions introduced by refactors related to static builds and adds a fixture that tests lazy loaded locales for static builds.

📝 Checklist

• I have linked an issue or discussion.
• I have added tests (if possible).
• I have updated the documentation accordingly.

[pkg-pr-new]

Open in Stackblitz

npm i https://pkg.pr.new/@nuxtjs/i18n@3323

commit: 765138a