[BUG] BsonRef attribute not working

[JonathanBout]

Version Latest (5.0.17)

Describe the bug The BsonRef attribute only sets the ID of the value, without actually filing it with data from the other collection.

Code to Reproduce FooBar.cs:

class Foo
{
    public string Name { get; set; } = "";
    [BsonId]
    public int Id { get; set; }
    [BsonRef]
    public Bar Bar { get; set; } = new();
}

class Bar
{
    public string Name { get; set; } = "";
    [BsonId]
    public int Id { get; set; }
}

Program.cs:

using LiteDB;

var db = new LiteDatabase(new ConnectionString
{
    Filename = ":memory:"
});

var barCollection = db.GetCollection<Bar>();
var fooCollection = db.GetCollection<Foo>();

var bar = new Bar
{
    Name = "The Foo.Bar Object"
};

// insert element and store it's Id
var id = barCollection.Insert(bar);

// reload the object by the specified id, this gives the correct object
bar = barCollection.FindById(id);

var foo = new Foo()
{
    Name = "The Foo Object",
    Bar = bar
};

// insert into foo collection
fooCollection.Insert(foo);

// retrieve foo again from collection
foo = fooCollection.Query().Single();

// foo.Bar.Name is empty
Console.WriteLine("Name: '{0}'", foo.Bar.Name);

db.Dispose();

Expected behavior The foo.Bar.Name contains "The Foo.Bar Object"