Remove all bytcode before running tox
Remove all bytcode before running tox

Currently __pycache__ directory, which also holds
python bytecode is not deleted when running tox.
The following patch proposes this trivial fix

TrivialFix
Depends-On: I5739cc1e3e42b10224c75fc3f936708c87574107
Change-Id: Ia6cd2cfe315a4e536871b355c7e87b03b362c4f5

openstack/kuryr,openstack/kuryr,celebdor/kuryr,celebdor/kuryr