ks-email-parser python update

[b1r3k]

lxml fails on 3.11 if lxml < 4 lxml >= 3 works

1. [x] find . -iname '.py' -not -path "/venv/*" -exec pyupgrade --py311-plus {} +
2. [x] transition to nose2
3. [x] enum changed behaviour of str()
4. [x] remove dependency on async_test
5. [x] transition to pytest - https://github.com/pytest-dev/nose2pytest
6. [ ] update travis CI

• [ ] what about different CI system?
  • [ ] github actions?
  • [ ] circle CI? (we already use it on mobile side)

7. [x] ansible playbook update
8. [ ] Optional: transition to pyproject.toml
9. [x] Optional: aiohttp update?

requires: https://github.com/KeepSafe/email-service/issues/419

Findings

• lxml 3.x does not compile on python 3.11 (at least when using python distribution provided by pyenv). lxml >= 4 compiles fine but tests may require some adjustment (output diff could have been caused by beautifulsoup in fact)