clippy: disable assert_is_empty lint

[cakebaker]

This PR disables the assert_is_empty lint introduced with Rust 1.99 as there are concerns about its usefulness: #14472 (comment) and #15022 (comment) .

As for me, I'm torn: something like assert_eq!(x, "") is an improvement whereas something like assert_eq!(x, [] as [_; 0]) is not.

[codspeed]

Merging this PR will degrade performance by 9.16%

⚡ 1 improved benchmark
❌ 1 regressed benchmark
✅ 391 untouched benchmarks
⏩ 54 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	three_39_bit_primes	533 ms	685.9 ms	-22.3%
⚡	Simulation	five_38_bit_primes	1.8 s	1.7 s	+6.21%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing cakebaker:clippy_disable_lint (eb0063e) with main (61a3e74)}

Footnotes

1. 54 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. ↩

[github-actions]

GNU testsuite comparison:

Congrats! The gnu test tests/id/setgid is no longer failing!

[cakebaker]

I merged this PR myself to bring the CI back to green. And it's trivial to reverse if we decide to want to enable the lint.