-r common.txt
coveralls==1.7.0
mock==2.0.0
pytest==4.4.0
pytest-cov==2.6.1
tox==3.8.3

-r common.txt
coveralls==1.7.0
mock==2.0.0
pytest==4.4.0
pytest-cov==2.6.1
tox==3.8.4

Update tox from 3.8.3 to 3.8.4
Update tox from 3.8.3 to 3.8.4