Add note about setting EVs from native libraries

[gewarren]

Fixes dotnet/docs#39448

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Tagging subscribers to this area: @dotnet/area-system-runtime

[mklement0]

Looks great for https://learn.microsoft.com/en-us/dotnet/api/system.environment, but you don't think the same remarks about the relationship with native libraries should be added to https://learn.microsoft.com/en-us/dotnet/fundamentals/runtime-libraries/system-environment-getenvironmentvariable as well?

[gewarren]

Looks great for https://learn.microsoft.com/en-us/dotnet/api/system.environment, but you don't think the same remarks about the relationship with native libraries should be added to https://learn.microsoft.com/en-us/dotnet/fundamentals/runtime-libraries/system-environment-getenvironmentvariable as well?

@mklement0 Yes, I do, but it's a separate repo, so separate PR: dotnet/docs#40029.

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[learn-build-service-prod]

Learn Build status updates of commit 2fd6c8c:

✅ Validation status: passed

File	Status	Preview URL	Details
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For more details, please refer to the build report.

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[BillWagner]

This LGTM @gewarren

I had a similar question as the related PR, once you decide what to do, let's