Extends coverage of the SpiralGroundCurve and fixes some bugs

[agalbachicar]

🎉 New feature

Part of #265 Goes on top of #271

Summary

Fixes some bugs, extends coverage, but still is tested against normalized curvatures. It is not functional yet a proper ground curve but provides a good testing base and leaves that to a future PR. The issue with normalization is that the general math resources considers the length from the curvature = 0 to a certain curvature and not a particular inter non-zero curvature extensions which makes it trickier to get it right. A future PR will address exactly that.

Test it

Via unit testing.

Checklist

• [x] Signed all commits for DCO
• [x] Added tests
• [ ] Added example and/or tutorial
• [ ] Updated documentation (as needed)
• [ ] Updated migration guide (as needed)
• [ ] Consider updating Python bindings (if it affects the public API)

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

[agalbachicar]

Declining in favor of a new implementation.