Package readmes are broken

[MSDN-WhiteKnight]

Description

Runtime packages have markdown readmes that should be rendered on NuGet gallery page. But latest preview version lost them, there's no package.md file in .nupkg, and NuGet gallery fallbacks to plaintext description. For example, for System.Reflection.Metadata 9.0.0-preview.6.24327.7 shows markdown readme, but 9.0.0-preview.7.24405.7 does not.

Reproduction Steps

Navigate to NuGet gallery page of the package, such as https://www.nuget.org/packages/System.Reflection.Metadata/9.0.0-preview.7.24405.7#readme-body-tab

Expected behavior

Should show markdown package readme, like for previous version:

Actual behavior

Shows plaintext description:

Regression?

Broken starting from latest version, 9.0.0-preview.7.24405.7

Known Workarounds

No response

Configuration

No response

Other information

No response

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