Automatic update from web-platform-tests [python3] Bring py3-flake8.ini up-to-date with py27-flake8.ini -- [taskcluster] Remove python2 tasks from Taskcluster CI Step 3 of https://github.com/web-platform-tests/rfcs/blob/master/rfcs/py_3.md -- [Azure Pipelines] Remove Python 2 from Azure Pipelines CI Step 3 of https://github.com/web-platform-tests/rfcs/blob/master/rfcs/py_3.md -- [python3] Update the bare minimum docs for dropping Py2 support There are probably references still remaining to Python 2, but this should remove the most egregious cases. -- wpt-commits: a3e8c672b0f5c63f0023d0f69871785788f85c2d, 7abcd71cdc84a5d17047079a1daceb04edb2da3e, 6b197f497940666c041294367adf52eddb2faa25, cc214bb6cd8a525ea104c7311e9f2f3b0cb65fbd wpt-pr: 27379