Vector sample code has issue which will cause out of range related exception

[lateapexearlyspeed]

In https://github.com/dotnet/docs/blob/main/docs/standard/simd.md, Vector sample code, it has logic of handling case about input array length not be integral multiple of Vector.Count (see green block),
but first half of code cannot handle it and will throw out of range related exception if happens (see red block)

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Document Details

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• ID: 9e0f3c8a-1548-40cd-1688-d574c0d1db1d
• Version Independent ID: 40f9283e-0200-4398-7dc3-00c2bca59e81
• Content: SIMD-accelerated types in .NET
• Content Source: docs/standard/simd.md
• Product: dotnet-fundamentals
• GitHub Login: @FIVIL
• Microsoft Alias: tagoo

[lateapexearlyspeed]

Hi, I raised PR to fix that, thanks.