test: all_identical agg make fuzzer faster

[joseph-isaacs]

.....

[codspeed-hq]

Merging this PR will degrade performance by 38.2%

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 1 improved benchmark
❌ 1 regressed benchmark
✅ 1204 untouched benchmarks
🆕 18 new benchmarks

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

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
🆕	Simulation	decimal_widen_scalar_loop	N/A	45.2 ms	N/A
🆕	Simulation	decimal_widen_assert_arrays_eq	N/A	90.4 ms	N/A
🆕	Simulation	fsl_nullable_all_identical	N/A	1.6 ms	N/A
🆕	Simulation	fsl_nullable_arrays_value_equal	N/A	1.9 ms	N/A
🆕	Simulation	fsl_nullable_assert_arrays_eq	N/A	148.2 ms	N/A
🆕	Simulation	fsl_nullable_scalar_loop	N/A	75 ms	N/A
🆕	Simulation	list_nullable_all_identical	N/A	2.7 ms	N/A
🆕	Simulation	list_nullable_assert_arrays_eq	N/A	55.7 ms	N/A
🆕	Simulation	list_nullable_scalar_loop	N/A	28.7 ms	N/A
🆕	Simulation	decimal_widen_all_identical	N/A	416.2 µs	N/A
🆕	Simulation	list_zero_copy_all_identical	N/A	2.5 ms	N/A
🆕	Simulation	decimal_widen_arrays_value_equal	N/A	1.8 ms	N/A
🆕	Simulation	list_zero_copy_arrays_value_equal	N/A	3.1 ms	N/A
🆕	Simulation	list_zero_copy_assert_arrays_eq	N/A	98.6 ms	N/A
🆕	Simulation	list_zero_copy_scalar_loop	N/A	50.4 ms	N/A
🆕	Simulation	struct_nullable_all_identical	N/A	868.8 µs	N/A
🆕	Simulation	struct_nullable_assert_arrays_eq	N/A	50.4 ms	N/A
🆕	Simulation	struct_nullable_scalar_loop	N/A	25.3 ms	N/A
❌	Simulation	chunked_bool_canonical_into[(1000, 10)]	31.3 µs	50.7 µs	-38.2%
⚡	Simulation	new_alp_prim_test_between[f64, 32768]	250.9 µs	192 µs	+30.7%

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_{Comparing ji/fuzzer-mem (0109fda) with develop (750457a)}