RequestDelegateGenerator enabled results in incorrect ApiParameterDescription.IsRequired for nullable array

### Is there an existing issue for this?

- [x] I have searched the existing issues

### Describe the bug

Basically the title. This translates to issues with the downstream OpenApi document, Swagger pages, etc.

### Expected Behavior

Enabling RDG should not affect how `ApiParameterDescription`s are generated

### Steps To Reproduce

Create a new dotnet 10 minimal API project.
```xml

net10.0
enable
enable
true

```

```cs
using Microsoft.AspNetCore.Mvc.ApiExplorer;

var builder = WebApplication.CreateBuilder(args);
var app = builder.Build();

app.MapGet("demo", ([AsParameters] Request request, IApiDescriptionGroupCollectionProvider descriptionGroupCollectionProvider) =>
{
var apiDescription = descriptionGroupCollectionProvider.ApiDescriptionGroups.Items.SelectMany(x => x.Items).Single();
return apiDescription.ParameterDescriptions.ToDictionary(p => p.Name, p => p.IsRequired);
});

await app.RunAsync();

public class Request
{
// When is enabled, this incorrectly determines this parameter is required. When disabled, it works correctly.
// This behaved correctly in dotnet 8 regardless of RDG
public int[]? OptionalIds { get; set; }

// This has correct nullability, regardless of RDG
public string? OptionalString { get; set; }
}
```

Note that the `IsRequired` for the `ApiParameterDescription` for the `OptionalIds` is incorrect, but only if RDG is set to enabled. I have so far only noticed this for nullable arrays, and not for other types (as included in the demo)

### Exceptions (if any)

None

### .NET Version

dotnet 10

### Anything else?

Let me know if the repro steps are not clear for some reason.