chore: bench stats.toJson()

[SyMind]

Summary

use codspeed to bench stats.toJson()

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).

[netlify]

✅ Deploy Preview for rspack canceled.

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🔨 Latest commit	2158430
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[codspeed-hq]

CodSpeed Performance Report

Merging #9569 will not alter performance

_{Comparing bench-stats-to-json (2158430) with main (3dc810e)}

🎉 Hooray! codspeed-rust just leveled up to 2.7.2!

A heads-up, this is a breaking change and it might affect your current performance baseline a bit. But here's the exciting part - it's packed with new, cool features and promises improved result stability 🥳!
Curious about what's new? Visit our releases page to delve into all the awesome details about this new version.

Summary

✅ 7 untouched benchmarks
🆕 1 new benchmarks

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
🆕	stats.toJson()	N/A	18.7 ms	N/A