Add pip environment markers to avoid installing some incompatible
dependencies under Python < 3.8.
pep8==1.7.1
flake8==5.0.4
-astroid==2.12.9
-pylint==2.15.2
+astroid==2.12.9; python_version >= '3.8'
+pylint==2.15.2; python_version >= '3.8'
codecov==2.1.12
-coverage==6.4.4
+coverage==6.4.4; python_version >= '3.8'
requests>=2.27.1
requests_mock==1.10.0
pytest==7.0.1
