Makefile: Add test commands to show missing coverage lines

[Zen-CODE]

This PR just makes it easier to run tests produce coverage report the details the lines not covered by tests.

This last option is very useful for targeting tests so we can optimize efforts to up coverage.

Maintainer merge checklist

• Title is descriptive/clear for inclusion in release notes.
• Applied a Component: xxx label.
• Applied the api-deprecation or api-break label.
• Applied the release-highlight label to be highlighted in release notes.
• Added to the milestone version it was merged into.
• Unittests are included in PR.
• Properly documented, including versionadded, versionchanged as needed.

[Zen-CODE]

@tshirtman I went with this approach because if we change the default via [tool.pytest.ini_options] in pyproject.toml, the simple test report becomes too verbose. Simple is sometime all you want. So adding extra command for more detail seems better.