phase: use `trackedphases` in `_getphaserevsnative`
Instead of manually listing secret and draft, simply use the `trackedphases`
constant. The constant is already used by `_getphaserevsnative`.
from .decoder import load, loads, CBORDecoder, CBORDecodeError # noqa
from .encoder import dump, dumps, CBOREncoder, CBOREncodeError, shareable_encoder # noqa
from .types import CBORTag, CBORSimpleValue, undefined # noqa