feat: Add flake8 E722 exception
feat: Add flake8 E722 exception

Add E722 exception since the check is now functional in flake8:
https://gitlab.com/pycqa/flake8/issues/361

Change-Id: I3938c99b9740962bba189404a17c0e7340f64b38

open-power-ref-design-toolkit/cluster-genesis,open-power-ref-design-toolkit/cluster-genesis