Support using Blazor pages with status code pages middleware

[danroth27]

If you try to use Blazor pages with the status code pages middleware you get unexpected behavior.

Repro steps:

• Create a Blazor Web App with global interactive server rendering
• Add the status code pages middleware to Program.cs: app.UseStatusCodePagesWithReExecute("/StatusCode/{0}");
• Add Components/Pages/StatusCode.razor:

@page "/StatusCode/{status:int}"

<PageTitle>@Status</PageTitle>

<h1>@Status</h1>

@code {
    [Parameter]
    public int Status { get; set; }
}

• Run the app and browser to a non-existent page, like /test

Expected result: Blazor status page renders for the 404 response.
Actual result: Blazor status page shows up briefly and then is replaced with a plain text "Not found" page.

We special case re-executed requests from the error handling middleware. We might need to do this for the status code page middleware as well.

Related issue for handling not found requests: #45654

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