increase iteration count on tests/bench-fast-api

[anonrig]

No description provided.

[codspeed-hq]

CodSpeed Performance Report

Merging #4525 will degrade performances by 79.9%

_{Comparing yagiz/double-iteration-count (c6ccbfe) with main (487fd1e)}

Summary

❌ 2 regressions
✅ 9 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
❌	SlowAPIWithLock[FastMethodFixture]	34.7 ms	93.5 ms	-62.89%
❌	SlowAPI[FastMethodFixture]	37.3 ms	185.7 ms	-79.9%