chore: setup.py for python3

2 jobs for branch/default in 43 seconds (queued for 4 seconds)
Status Name Job ID Coverage
  Tests
failed py27 #562893
py2 tests

00:00:43

failed py27 #562892
tests py2

00:00:53

 
Name Stage Failure
failed
py27 Tests
WARNING: You are using pip version 20.0.2; however, version 20.3.4 is available.
You should consider upgrading via the '/builds/cubicweb/cubes/email/.tox/py27/bin/python -m pip install --upgrade pip' command.

=================================== log end ====================================
ERROR: could not install deps [-rrequirements-test.txt, git+https://github.com/psycojoker/pytest-capture-deprecatedwarnings]; v = InvocationError(u'/builds/cubicweb/cubes/email/.tox/py27/bin/python -m pip install -rrequirements-test.txt git+https://github.com/psycojoker/pytest-capture-deprecatedwarnings', 1)
___________________________________ summary ____________________________________
ERROR: py27: could not install deps [-rrequirements-test.txt, git+https://github.com/psycojoker/pytest-capture-deprecatedwarnings]; v = InvocationError(u'/builds/cubicweb/cubes/email/.tox/py27/bin/python -m pip install -rrequirements-test.txt git+https://github.com/psycojoker/pytest-capture-deprecatedwarnings', 1)
Cleaning up file based variables
ERROR: Job failed: command terminated with exit code 1