[Benchmark X64] [AnsBalin] Fix size used for vectorization check in BitArray (#111558)

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Job completed in 12 minutes 42 seconds.

Using arguments: benchmark BitArrayCopyToBoolArray https://github.com/MihaZupan/performance/tree/bitarray -NoPRLink

System.Collections.Tests.Perf_BitArray

BenchmarkDotNet v0.14.1-nightly.20250107.205, Linux Ubuntu 22.04.5 LTS (Jammy Jellyfish)
AMD EPYC 9V74, 1 CPU, 16 logical and 8 physical cores
  Job-HZJVEQ : .NET 10.0.0 (42.42.42.42424), X64 RyuJIT AVX-512F+CD+BW+DQ+VL+VBMI
  Job-YOHLJP : .NET 10.0.0 (42.42.42.42424), X64 RyuJIT AVX-512F+CD+BW+DQ+VL+VBMI
OutlierMode=Default  PowerPlanMode=00000000-0000-0000-0000-000000000000  IterationTime=250ms
MaxIterationCount=20  MemoryRandomization=Default  MinIterationCount=15
WarmupCount=1

Method	Toolchain	Size	Mean	Error	Ratio	Allocated	Alloc Ratio
BitArrayCopyToBoolArray	Main	16	5.856 ns	0.0497 ns	1.00	-	NA
BitArrayCopyToBoolArray	PR	16	5.866 ns	0.0967 ns	1.00	-	NA
BitArrayCopyToBoolArray	Main	32	9.290 ns	0.1164 ns	1.00	-	NA
BitArrayCopyToBoolArray	PR	32	9.614 ns	0.1803 ns	1.04	-	NA
BitArrayCopyToBoolArray	Main	63	50.185 ns	0.1043 ns	1.00	-	NA
BitArrayCopyToBoolArray	PR	63	50.089 ns	0.1376 ns	1.00	-	NA
BitArrayCopyToBoolArray	Main	64	13.466 ns	0.2185 ns	1.00	-	NA
BitArrayCopyToBoolArray	PR	64	14.243 ns	0.1288 ns	1.06	-	NA
BitArrayCopyToBoolArray	Main	128	23.929 ns	0.0333 ns	1.00	-	NA
BitArrayCopyToBoolArray	PR	128	22.581 ns	0.0072 ns	0.94	-	NA
BitArrayCopyToBoolArray	Main	256	44.228 ns	1.2290 ns	1.00	-	NA
BitArrayCopyToBoolArray	PR	256	44.367 ns	1.1427 ns	1.00	-	NA

Artifacts:

• BDN_Artifacts.zip (41 KB)
• results.md (2 KB)

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