manifest: use explicit None checking in `_loaddifflazy` This helps pytype to understand what is going here with `v2` type.

manifest: use explicit None checking in `_loadlazy` This help pytype to understand what is going on with `v` type.

manifest: clear `_lazydirs` in place in `_loadalllazy` This avoid resetting the type of the dictionary in pytype eyes. This is consistent with the way the dictionary is cleared bits by bits in `_loadalllazy` Having more accurate code will help pytype. We do it in advance to help bisecting and avoid drowning them in the future type annotation noise.

manifest: use tuple for `delta` in `fastdelta` This make the list content consistent and will help type annotation.

manifest: expose a version of the Class without interface decorator The decorator confuse Pytype. Having the "raw" python class exposed will also helps pytype when it get replaced by a native implementation. At least until we start using `typing.Protocol` in the future.

pytype: stop ignoring manifest.py pytype no longer complains about the file contents.

manifest: align some vfs option access on the fact we might not have options This make the usage consistent with the other option. Caught by pytype.

manifest: adds some type things for manifestdict.added This appeases pytype.

manifest: type and fix unhexlify Some part of that function seems to date back from Python 2. It raise question about whether this function is useful or not, but let us just fix it for now. This was caught by pytype.

docker-pytype: use version v2.1 of the CI image It use a more recent pytype as far as I understand.