shelve: consistently convert exception to bytes via `stringutil.forcebytestr` The other two places in this module use this, and past experience shows that this method does a nicer job. I'm not sure why we're converting to bytes here- `KeyError` is built-in and will have str attrs, and `RepoLookupError` is a subclass of the built-in `Exception` class (not `errors.Error`, which is allegedly the baseclass for all Mercurial exceptions).

from typing import (
    List,
    Tuple,
)

version: int

def bdiff(a: bytes, b: bytes) -> bytes: ...
def blocks(a: bytes, b: bytes) -> List[Tuple[int, int, int, int]]: ...
def fixws(s: bytes, allws: bool) -> bytes: ...
def splitnewlines(text: bytes) -> List[bytes]: ...
def xdiffblocks(a: bytes, b: bytes) -> List[Tuple[int, int, int, int]]: ...