Update flake8 version to 3.7.7 in requirements.txt
Update flake8 version to 3.7.7 in requirements.txt

seleniumbase/SeleniumBase,mdmintz/SeleniumBase,seleniumbase/SeleniumBase,mdmintz/SeleniumBase,seleniumbase/SeleniumBase,mdmintz/SeleniumBase,seleniumbase/SeleniumBase,mdmintz/SeleniumBase