typing: add `from __future__ import annotations` to remaining source files...
typing: add `from __future__ import annotations` to remaining source files
Most of these look newer than when the original imports referenced in the
previous commit were dropped, so these weren't covered by the backout. These
were found with:
hg files mercurial hgext hgext3rd -I '**.py' -X '**/thirdparty' \
| xargs grep -L 'from __future__ import annotations'
All of the `__init__.py` files that finds are empty, so those were ignored and
the rest manually edited.
