coverage>=4.5.3,<5.2
docutils>=0.15,<0.17
flake8>=3.7,<3.8
pytest>=3.6,<5.5
pytest-cov>=2.7.1,<2.9
isort>=4.3.20,<4.4

coverage>=4.5.3,<5.2
docutils>=0.15,<0.17
flake8>=3.7,<3.9
pytest>=3.6,<5.5
pytest-cov>=2.7.1,<2.9
isort>=4.3.20,<4.4

Update flake8 requirement from <3.8,>=3.7 to >=3.7,<3.9
Update flake8 requirement from <3.8,>=3.7 to >=3.7,<3.9

Updates the requirements on [flake8](https://gitlab.com/pycqa/flake8) to permit the latest version.
- [Release notes](https://gitlab.com/pycqa/flake8/tags)
- [Commits](https://gitlab.com/pycqa/flake8/compare/3.7.0...3.8.0)

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>