refactor(deno-deploy): use Deno.serve

[markthree]

🔗 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

deno deploy already supports Deno.serve and std/http/serve is deprecated.

This small change will theoretically reduce nitro's cold-start time during deno deploy and the service will perform better! 🥰

Ref:

• deno.com/deploy/changelog#2023-07-06
• deno.com/blog/v1.38#updates-to-stdhttp

📝 Checklist

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

[pi0]

Thanks!