Exclude css isolation assets from `dotnet publish`

> Originally posted at [StackOverflow](https://stackoverflow.com/q/72448577/9971404), but there seems no way to control this. So I'm adding as a feature request. Thank you.
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> ### Is there an existing issue for this?
> * [x] I have searched the existing issues
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> ### Is your feature request related to a problem? Please describe the problem.
> I'm using RazorPages (on ASP.NET Core 6) and "css isolation". The css files are generated at `obj/{Debug,Release}/net6.0/scopedcss/Pages/`, and are included when performing a `dotnet publish`.
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> I also use Webpack, so I don't need to publish those css files (they are already bundled by Webpack).
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> I added variations of all of these to my `Project.csproj` without success:
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> $(DefaultItemExcludes);obj/*/*/scopedcss/**/*
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> These (and variations of them in every combination) did not work.
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> ### Describe the solution you'd like
> Please provide a way to exclude css isolation assets from `dotnet publish`.
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> ### Additional context
> My non-ideal workaround is to delete the files after publish:
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Tracking an [issue](https://github.com/dotnet/aspnetcore/issues/41961) created on /aspnetcore, so it can be fixed here in the sdk instead.