feat: drop six

BREAKING CHANGE: not compatible with python2 anymore.
5 jobs for !14 with topic/default/drop-python2 in 3 minutes and 51 seconds (queued for 4 minutes)
latest detached
Status Name Job ID Coverage
  Lint
passed check-manifest #289172

00:00:27

passed flake8 #289171

00:00:24

passed safety #289174

00:00:48

passed yamllint #289173

00:00:30

 
  Tests
passed py3 #289175

00:02:07