Expand Testing

[kwabenantim]

Summary

Tests are currently run for the shapes example, but don't cover all use cases.

TODO

• Test on multiple Python versions (3.8 - 3.12).
• Update example shapes project CMake configuration.
• Update pybind11 version in example shapes project.
• Add testing with flake8
• Measure current test coverage.
• Increase test coverage to 25%.
• Increase test coverage to 50%.
• Increase test coverage to 75%.
• Increase test coverage to 100%.