fix(vercel, netlify): keep default behavior for static and swr to isr mapping

[danielroe]

🔗 Linked issue

resolves #1145

❓ 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)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

This adds a compatibility layer to keep user config working if using swr or static on Vercel + Netlify, with a deprecation warning.

📝 Checklist

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

[codecov]

Codecov Report

Merging #1155 (ba1a692) into main (b320208) will increase coverage by 0.15%.
The diff coverage is 92.98%.

@@            Coverage Diff             @@
##             main    #1155      +/-   ##
==========================================
+ Coverage   76.81%   76.96%   +0.15%     
==========================================
  Files          67       67              
  Lines        6556     6613      +57     
  Branches      694      720      +26     
==========================================
+ Hits         5036     5090      +54     
- Misses       1519     1522       +3     
  Partials        1        1              

Impacted Files	Coverage Δ
src/presets/vercel.ts	93.81% <92.59%> (+0.26%)	⬆️
src/presets/netlify.ts	78.24% <93.33%> (+2.43%)	⬆️

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[pi0]

Shall we handle static rule flag too?