Use stricter flake8 plugins in pre-commit

  - repo: https://gitlab.com/pycqa/flake8
    rev: 3.7.8
    hooks:
      - id: flake8
        language_version: python3.7
        additional_dependencies:
        - flake8-bugbear
        - flake8-deprecated
        - flake8-comprehensions
        - flake8-isort
        - flake8-quotes
        - flake8-mutable
        - flake8-todo