fix(cache): try to call event.waitUntil

[pi0]

🔗 Linked issue

#1420

❓ 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

Based on #1421, try to call event.waitUntil for the cache update operation if the first parameter in defineCachedFunction is an event and always for defineCachedEventHandler.

Previously we were using a dangling background promise which was not being ended on Cloudflare workers.

(this is an experimental fix without introducing new API)

📝 Checklist

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

[codecov]

Codecov Report

Merging #1422 (12ca201) into main (574d892) will not change coverage.
The diff coverage is n/a.

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  Files          71       71           
  Lines        7317     7317           
  Branches      729      729           
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  Hits         5621     5621           
  Misses       1695     1695           
  Partials        1        1