[Blazor] Explicit call to `UseRouting()` may break some scenarios

[MackinnonBuck]

There have been multiple issue reports where an explicit call to UseRouting() in a Blazor Web App causes some functionality to stop working.

Examples:

• .NET 8 migration from WASM to Blazor Web App - environment not set correctly #53832
• Blazor WebApp Wasm Hot Reload does not work with UseRouting #52339

We should investigate the root cause and determine whether there needs to be a fix in the framework.