debugbackupbundle: use new context manager for silencing the ui A difference between setting `ui.quiet` and using `ui.silent()` is that the latter also silences `ui.write()` calls. That's practically always what one wants, including here, I think. Differential Revision: https://phab.mercurial-scm.org/D10885

from typing import Optional

version: int

def b85encode(text: bytes, pad: Optional[int]) -> bytes: ...
def b85decode(text: bytes) -> bytes: ...