`EntityTypeConfiguration<TEntityType>.HasKey` does not allow a nested expression

Assemblies affected

Microsoft.AspNetCore.OData 8.0.12

Describe the bug

EntityTypeConfiguration<TEntityType>.HasKey does not allow a nested expression.

I'm trying to set up odata with DTOs, mapping to EF Core queries with Automapper.
My DTO, which I'm trying to use as the OData entity, is set up differently than the EF Core entity, it has a nested type with the general information, which has the id on it.
However, HasKey only allows member expressions, so this won't work:

modelBuilder.EntityType<Dto>()
        .HasKey(a => a.General.Id);

Data Model

For the purposes of this issue, consider a reduced version:

public class Dto
{
    public DtoGeneral General { get; set; }
}
public class DtoGeneral
{
    public int Id { get; set; }
}

Additional Notes

Are nested things even allowed btw?
EF Core has owned types, are all types that aren't entities considered owned in OData?
My model has quite a bunch of nested types, It'd be unfortunate if I had to inline all that.

Start at the EntityTypeConfiguration.HasKey entry point and trace how the provided member expression is validated. Use the nested Dto and DtoGeneral example to determine whether nested keys are supported, then verify the behavior against the issue's OData configuration scenario.