Update pytest-cov to 3.0.0#26

bors[bot] merged 1 commit intomasteraragilar/spaceplot:masterfrom

pyup-update-pytest-cov-2.12.1-to-3.0.0aragilar/spaceplot:pyup-update-pytest-cov-2.12.1-to-3.0.0Copy head branch name to clipboard