[release/9.0-staging] Support generic fields in PersistedAssemblyBuilder

[github-actions]

Backport of #110372 to release/9.0-staging

/cc @steveharter

Customer Impact

• Customer reported
• Found internally

[Select one or both of the boxes. Describe how this issue impacts customers, citing the expected and actual behaviors and scope of the issue. If customer-reported, provide the issue number.]

Regression

• Yes
• No

[If yes, specify when the regression was introduced. Provide the PR or commit if known.]

Testing

[How was the fix verified? How was the issue missed previously? What tests were added?]

Risk

[High/Medium/Low. Justify the indication by mentioning how risks were measured and addressed.]

IMPORTANT: If this backport is for a servicing release, please verify that:

• The PR target branch is release/X.0-staging, not release/X.0.

Package authoring no longer needed in .NET 9

IMPORTANT: Starting with .NET 9, you no longer need to edit a NuGet package's csproj to enable building and bump the version.
Keep in mind that we still need package authoring in .NET 8 and older versions.

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