Create a unit test for PAL_GetLogicalProcessorCacheSizeFromOS

[mangod9]

There was a bug specific for Alpine Linux where PAL_GetLogicalProcessorCacheSizeFromOS would return 0. We should add a unittest or an assert to ensure we dont regress this behavior.

The fix was part of this PR: #41532

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[adamsitnik]

@mangod9 thank you!