Fix #17903

[vzarytovskii]

Fixes #17903. Test is missing, checking the waters.

The idea of the fix is pretty dumb. The copyOfStruct address is leaking outside the scope which trips the locals reuse algorithm. After looking more into it, and chatting with Don, I decided to mark copyOfStruct as no-reuse, but keeping it in cgbuf cache.

[github-actions]

❗ Release notes required

@vzarytovskii,

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[vzarytovskii]

/run fantomas

[github-actions]

Ran fantomas: https://github.com/dotnet/fsharp/actions/runs/11899215330

[0101]

A test would be nice.