docs: fix nuxtlabs studio url in migration

[nickspaargaren]

❓ Type of change

• 📖 Documentation (updates to the documentation or readme)
• 🐞 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)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

Fixes the link to the Studio module in https://content.nuxt.com/docs/getting-started/migration#nuxt-studio-integration.

📝 Checklist

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

[pkg-pr-new]

npm i https://pkg.pr.new/@nuxt/content@3150

commit: 91c9b92

[farnabaz]

Thanks