docs: remove auto-imported defineNitroConfig

[Barbapapazes]

🔗 Linked issue

❓ 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

Since the defineNitroConfig is auto-imported, I think that we could safely remove import from examples.

📝 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	76f0cc1

[codecov]

Codecov Report

Merging #1441 (8fdd59d) into main (e87e2ba) will not change coverage.
The diff coverage is n/a.

❗ Current head 8fdd59d differs from pull request most recent head 76f0cc1. Consider uploading reports for the commit 76f0cc1 to get more accurate results

@@           Coverage Diff           @@
##             main    #1441   +/-   ##
=======================================
  Coverage   76.17%   76.17%           
=======================================
  Files          73       73           
  Lines        7437     7437           
  Branches      728      728           
=======================================
  Hits         5665     5665           
  Misses       1771     1771           
  Partials        1        1           

[Hebilicious]

Thanks for making this PR !
I have a slight preference for the way things currently are, but I'm not too opinionated either way. @pi0 will decide.

[pi0]

Thanks!