pytest tips and tricks for a better testsuite

We'll cover things like:

• Recommended pytest settings for more strictness
• What's xfail and why is it useful?
• How to mark an entire test file or single parameters
• Ways to deal with parametrize IDs and syntax
• Useful built-in pytest fixtures
• Caching for fixtures
• Using fixtures implicitly
• Advanced fixture and parametrization topics
• How to customize fixtures behavior based on markers or custom CLI arguments
• If time permits: Short intro to writing pytest plugin and to property-based testing with Hypothesis

To prepare, please clone the GitHub repository and follow the setup steps in the README.