refactor: removing unnecessary references in fn signatures

[nyurik]

Address all suggestions of clippy::trivially_copy_pass_by_ref

Seems cleaner, and I wonder if perf would be affected

[codspeed-hq]

Merging this PR will degrade performance by 3.3%

❌ 1 regressed benchmark
✅ 283 untouched benchmarks
⏩ 38 skipped benchmarks¹

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

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	du_max_depth_balanced_tree[(6, 4, 10)]	26.8 ms	27.7 ms	-3.3%

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_{Comparing nyurik:refs (c0f28ba) with main (26a29ca)}

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. ↩

[sylvestre]

Could you please update the clippy configuration to make sure we don't regress in the future

[nyurik]

Could you please update the clippy configuration to make sure we don't regress in the future

already done -- this PR removes trivially_copy_pass_by_ref in Cargo.toml

[sylvestre]

i missed it, sorry