Bugfix for Array.insertManyAt returns original array for empty inserion (#18352)

[muqiuhan]

Description

Use array.Clone() to fix the bug that Array.insertManyAt directly returning source array when the values inserted are empty.

• Fix Array.insertManyAt returns original array for empty insertion #18352

Checklist

• Test cases added
• Performance benchmarks added in case of performance changes
• Release notes entry updated

[github-actions]

❗ Release notes required

@muqiuhan,

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Change path	Release notes path	Description
src/FSharp.Core	docs/release-notes/.FSharp.Core/9.0.300.md	No release notes found or release notes format is not correct

[psfinaki]

Hi @muqiuhan - thanks for the contribution. Could you please add a test for the fix?

[muqiuhan]

On Mon, 03 Mar 2025 03:21:35 -0800 Petr ***@***.***> wrote: psfinaki left a comment (dotnet/fsharp#18353) Hi @muqiuhan - thanks for the contribution. Could you please add a test for the fix?

Sure, I added a test to cover this change in `Array.insertManyAt`

[albert-du]

👍