Added option for generating private documentation

[IanLilleyT]

How to use:

npm run generateDocumentation -- --private

This will generate documentation for all @private elements. It's intended for local development purposes only.

This PR also adds the --pedantic flag which treats warnings as errors. See https://jsdoc.app/about-commandline.html. This would have caught #10208. Are there any downsides to adding this flag?

[cesium-concierge]

Thanks for the pull request @IanLilleyT!

• ✔️ Signed CLA found.
• ❔ 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.

[ggetz]

Hi @IanLilleyT, what's the motivation behind generating docs for the private symbols? Just for verification purposes?

[IanLilleyT]

Yep, just for verification purposes. Trying to make sure I'm being careful

[ggetz]

Cool, works for me. Thanks @IanLilleyT !