Fixes camera not tracking trackedEntity with HeightReference

[sanjeetsuhag]

Fixes #10804

The cause of this issue was that when a TerrainProvider with availability was used, the ModelVisualizer.prototype.getBoundingSphere was returning the result from its previous invocation. The fix was to simply clear the previous result in the _modelHash object for a given entity.

See this Sandcastle - test with different HeightReference types and with/without CesiumTerrainProvider.

[cesium-concierge]

Thanks for the pull request @sanjeetsuhag!

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  • If this change updates the public API in any way, please add a bullet point to CHANGES.md.
• ❔ 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.

[ggetz]

Awesome, thanks for the quick fix @sanjeetsuhag! Would it be possible to write a unit test for this case?

[sanjeetsuhag]

@ggetz Updated - added checks to ensure that the data in modelHash is reset in all cases.

[ggetz]

Thanks @sanjeetsuhag!