Document blazor msbuild configuration options

There are a bunch of knobs available to config blazor projects, that I could not find documented anywhere.

I raised the issue before and things were moved around a bit, so this issue is to ensure the old issue doesn't get lost.

The old issue is at https://github.com/dotnet/AspNetCore.Docs/issues/24026

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* ID: aa484235-d872-f50e-96fc-aa5b4a2a42fa
* Version Independent ID: 871c22e0-65a2-f3a4-41b9-f050489dba7a
* Content: [.NET project SDK overview](https://docs.microsoft.com/en-us/dotnet/core/project-sdk/overview)
* Content Source: [docs/core/project-sdk/overview.md](https://github.com/dotnet/docs/blob/main/docs/core/project-sdk/overview.md)
* Product: **dotnet-fundamentals**
* GitHub Login: @gewarren
* Microsoft Alias: **gewarren**