This commit adds flake8-bugbear to the patching tox test in order to
identify potential py3 issues and address them now.
Change-Id: I2219e61eff16cc69afa50d554e9f1dd0bb2f1517
Story: 2007050
Task: 38146
Signed-off-by: Don Penney <don.penney@windriver.com>