Include dotnet/hostfxr/hostpolicy symbols in Microsoft.NETCore.App.Host/Runtime packages

[elinor-fung]

We're currently relying on some old host packages to get symbols published. This adds those symbols to existing shipping packages.

• Add symbols for hostfxr and hostpolicy to the Microsoft.NETCore.App.Runtime package
• Add symbols for dotnet to the Microsoft.NETCore.App.Host package
• Fix non-Windows symbols not being included in Microsoft.NETCore.App.Host package

This should allow us to remove the old packages: #35244

[ghost]

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Issue Details

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We're currently relying on some old host packages to get symbols published. This adds those symbols to existing shipping packages.

• Add symbols for hostfxr and hostpolicy to the Microsoft.NETCore.App.Runtime package
• Add symbols for dotnet to the Microsoft.NETCore.App.Host package
• Fix non-Windows symbols not being included in Microsoft.NETCore.App.Host package

This should allow us to do remove the old packages: #35244

Author:	elinor-fung
Assignees:	elinor-fung
Labels:	area-Host
Milestone:	-

[elinor-fung]

@agocke @jkoritzinsky could one of you take a look here? This is just adding the host symbols to existing packages. I plan to do a follow-up to remove the old packages after this.