docs(storage): fix unstorage links

[kasperkronborg]

🔗 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

I know there is already a PR with storage docs changes (#2086), but I could see that it did not contain fixes for the "dead" links to unstorage, so I went ahead and fixes them in this PR.

📝 Checklist

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

[nuxt-studio]

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[pi0]

Thanks good spot!

/cc @atinux we need to add redirects :D

[atinux]

Redirects are added but still good to update links :)