UseStaticFiles does not work with spaces encoded as plus signs

### Is there an existing issue for this?

- [x] I have searched the existing issues

### Describe the bug

`app.UseStaticFiles()` returns 404 for file names that contain spaces and the browser requests them using `+` rather than `%20`.

Such links are easy to come across since `HttpUtility.UrlEncode` uses `+` to encode spaces. `HttpUtility.UrlPathEncode` which encodes spaces as `%20` is [documented](https://learn.microsoft.com/en-us/dotnet/api/system.web.httputility.urlpathencode) as do not use.

### Expected Behavior

The `+` sign to be decoded into space and the files served.

### Steps To Reproduce

1. Create a new ASP.NET project
2. Put a file with space in the wwwroot folder.
3. Request it using `+` for space.

### Exceptions (if any)

_No response_

### .NET Version

10.0.100-rc.2.25502.107

### Anything else?

Running on Microsoft.AspNetCore.App 8.0.21.