docs: add instructions for using nuxt edge release channel

[luc122c]

🔗 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

While attempting to test the latest Nitro edge release, I couldn't get Nuxt to build using the edge version, despite the console telling me that I was on the edge release. See #1663. @pi0 suggested to use the Nuxt edge release as it includes the Nitro edge release.

This PR adds a code example and a link to the relevant Nuxt docs.

📝 Checklist

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

[nuxt-studio]

✅ Live Preview ready!

Name	Edit	Preview	Latest Commit
nitro	Edit on Studio ↗︎	View Live Preview	56451a4

[codecov]

Codecov Report

Merging #1688 (56451a4) into main (ab15724) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #1688   +/-   ##
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  Coverage   77.79%   77.79%           
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  Files          76       76           
  Lines        7836     7836           
  Branches      805      805           
=======================================
  Hits         6096     6096           
  Misses       1738     1738           
  Partials        2        2