cext: remove Python 2 module initializer functions
We no longer need these since we dropped support for Python 2.
Differential Revision: https://phab.mercurial-scm.org/D12221
from typing import (
List,
)
version: int
class mpatchError(Exception): ...
def patches(text: bytes, bins: List[bytes]) -> bytes: ...
def patchedsize(orig: int, data: bytes) -> int: ...