`collections.namedtuple`: support passing `typename` and `field_names` by keyword argument

Pyright supports this, so ideally I think we would too (though mypy and pyrefly do not):

```py
from collections import namedtuple

NT = namedtuple(typename="NT", field_names="x y")
NT(x=1, y=2)
```

Note that these can only be passed by keyword for `collections.namedtuple`, not for `typing.NamedTuple`.

Cc. @charliermarsh 