Creating a DictConfig from another drops node types

[omry]

test:

@dataclass
class User:
    name: str
    age: int

cfg1 = OmegaConf.create(module.User(name="James Bond", age=7))
with pytest.raises(ValidationError):
  cfg1.age = "not a number"

cfg2 = OmegaConf.create(cfg1)
with pytest.raises(ValidationError):
  cfg2.age = "not a number"