Support YamlConverterAttribute in attribute overrides

[ChristopherMann]

This PR adds support for the YamlConverterAttribute in the attribute overrides. The allows the configuration of the deserializer as follows:

new DeserializerBuilder()
    .WithAttributeOverride<OuterClassWithoutAttribute>(
        c => c.Value,
        new YamlConverterAttribute(typeof(AttributedTypeConverter)))
    .WithTypeConverter(new AttributedTypeConverter())
    .Build();

This way, the YamlConverterAttribute is more aligned with e.g. the YamlMemberAttribute and it is possible to specify a custom converter for a specific property without modifying the model classes.