fix(module): allow using without recommended modules

[qwerzl]

🔗 Linked issue

❓ 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 #979, Resolves #883. This PR does two things:

1. If the two modules (@nuxtjs/tailwindcss or @nuxtjs/color-mode) are not installed, then we will not call installModule(), instead we'll give a warning about this.
2. Added a config option (suppressMissingModuleWarning) to suppress the above warning.

📸 Screenshots (if appropriate)

N/A

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.