Update reviewbot for flake8-3
In 3.0, flake8 does not have anymore an engine module. There is an api.legacy.
This instance will be upgraded to Heptapod 1.3.3 (GitLab 16.9.6) on 2023-04-25 at 18:00 UTC+2
In 3.0, flake8 does not have anymore an engine module. There is an api.legacy.