[Blazor] Error page support

[danroth27]

When I try to trigger the exception handler middleware by throwing an exception from a Blazor Web App I get an exception about RemoveNavigationManager being already initialized.

Repro steps:

• Install .NET 8 Preview 7
• Create a Blazor Web App
• Add a Pages/Error.razor component (see Blazor Web App is missing an error page #49853)
• In Index.razor add an OnInitialized method that throws an exception
• Change the launch environment to Production
• Run the app and browse to the home page

Expected result: Exception is thrown and handled by the exception handler middleware so the error page is rendered.
Actual result:

fail: Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware[3]
      An exception was thrown attempting to execute the error handler.
      System.InvalidOperationException: 'RemoteNavigationManager' already initialized.
         at Microsoft.AspNetCore.Components.NavigationManager.Initialize(String baseUri, String uri)
         at Microsoft.AspNetCore.Components.Server.Circuits.RemoteNavigationManager.Initialize(String baseUri, String uri)
         at Microsoft.AspNetCore.Components.Endpoints.EndpointHtmlRenderer.InitializeStandardComponentServicesAsync(HttpContext httpContext, Type componentType, String handler, IFormCollection form)
         at Microsoft.AspNetCore.Components.Endpoints.RazorComponentEndpointInvoker.RenderComponentCore()
         at Microsoft.AspNetCore.Components.Rendering.RendererSynchronizationContext.<>c.<<InvokeAsync>b__9_0>d.MoveNext()
      --- End of stack trace from previous location ---
         at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddlewareImpl.HandleException(HttpContext context, ExceptionDispatchInfo edi)