Fix deprecation warnings with V8 14.4

[fhanau]

PropertyCallbackInfo<>::This() is now deprecated, HolderV2() is to be used instead.

Draft for now – causes tests to fail with "TypeError: Illegal invocation: function called with incorrect this reference".

[codspeed-hq]

CodSpeed Performance Report

Merging this PR will degrade performance by 17.94%

_{Comparing felix/011326-fix-v8-warnings (b9ac257) with main (5f00731)}

Summary

⚡ 1 improved benchmark
❌ 1 regressed benchmark
✅ 138 untouched benchmarks
⏩ 38 skipped benchmarks¹

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

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
⚡	simpleStringBody[Response]	21.7 µs	19.2 µs	+12.93%
❌	jsonResponse[Response]	34.9 µs	42.5 µs	-17.94%

Footnotes

1. 38 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[fhanau]

Closing this PR – solving the issue will be more complex than just using HolderV2(), see #6003 for ongoing work.