Update BitArray.CopyTo to use the xplat intrinsics

[tannergooding]

As per #114818 (comment), BitArray.CopyTo could benefit from using the cross platform intrinsic APIs rather than the platform specific ones.

This can be achieved by swapping out these API calls:

• Avx512BW.IsSupported -> Vector512.IsHardwareAccelerated
• Avx512BW.Shuffle(x, y) -> Vector512.Shuffle(x, y)
• Avx512F.And(x, y) -> x & y
• Avx512BW.Min(x, y) -> Vector512.Min(x, y)
• Avx512F.Store(x, y) -> y.Store(x)

Similar changes could also be made to the Avx2 path (using Vector256) and so on.

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