fix: rectanglePromise.then is not a function

[hongfaqiu]

In the latest Cesium version, v1.107.0, an issue has occurred when using viewer.flyTo to navigate to an ImageryLayer.

[cesium-concierge]

Thanks for the pull request @hongfaqiu!

• ❌ Missing CLA.
  • Please send in a Contributor License Agreement (CLA) and comment back here to let us know to check this!
• ❔ CHANGES.md was not updated.
  • 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.

[hongfaqiu]

Thanks for the pull request @hongfaqiu!

• ❌ Missing CLA.

  • Please send in a Contributor License Agreement (CLA) and comment back here to let us know to check this!

• ❔ CHANGES.md was not updated.

  • 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.

CLA sended

[ggetz]

Thank you @hongfaqiu! Could you please update CHANGES.md with a summary of the fix?

[hongfaqiu]

@ggetz Thank you for reviewing! I wrote the fix summary in the 'Fixes 🔧' column of version 1.107. I'm not sure if this is the correct way to do it.

[ggetz]

Thanks again @hongfaqiu ! I moved your change to the next release.

I also noticed that we didn't have a unit test to cover this case. I went ahead and added one. This should be good to merge in as soon as CI passes.

[hongfaqiu]

Thanks again @ggetz! I am delighted to be one of the contributors to this great project!