Fix GeoJSON Polygon Overlapping problem

[shehzan10]

Thanks @hpinkos for the suggestion - Using the cartographic points instead of projecting to tangent plane fixed the overlap.

This was caused by the triangulation detecting that a polygon was inside rather than outside the boundary.

Fixes #8042.

[cesium-concierge]

Thanks for the pull request @shehzan10!

• ✔️ Signed CLA found.
• ❔ Unit tests were not updated.
  • Make sure you've updated tests to reflect your changes, added tests for any new code, and ran the code coverage tool.

Reviewers, don't forget to make sure that:

• Cesium Viewer works.
• Works in 2D/CV.
• Works (or fails gracefully) in IE11.

[hpinkos]

Flawless PR, thanks @shehzan10! This one is a little difficult to unit test, but the fix is not likely to get reverted by accident so I'm going to merge this.