[Pre6] Blazor preloading change

[maraf]

[EDIT by guardrex to add the article metadata]

PR dotnet/aspnetcore#62225 (preview 6)

We changed how we do preloading. Instead of using link headers, we have switched to <LinkPreload /> component.
The reasons for this change are

1. Having a component, we can rely on <base href="..." /> tag to correctly identify the "root" of blazor application within ASP.NET Core app.
2. Having a component, it's easy to turn the feature off, just remove the component.

The change requires a change to user applications by placing component somewhere near after the base tag

<base href="/" />
+<LinkPreload />

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Document Details

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• ID: 7b8429b0-dbb8-9768-572c-8fa04ec42146
• Version Independent ID: 7b8429b0-dbb8-9768-572c-8fa04ec42146
• Platform ID: da71d702-4227-7e6c-feb8-df36315ffbe4
• Content: Host and deploy ASP.NET Core server-side Blazor apps
• Content Source: aspnetcore/blazor/host-and-deploy/server/index.md
• Service: aspnet-core
• Sub-service: blazor
• GitHub Login: @guardrex
• Microsoft Alias: wpickett