per naming convention and #4921 this should make this `Rectangle.validate` private.

[hotpocket]

Description

The Rectangle.validate function is only called in pragmas and has thus been an empty function call. Per issue #4921 it was suggested to make this private, presumably so that this behavior is explicit.

Testing plan

All tests pass that were previously passing. There was one test that failed on my Ubuntu 22.04.05 OS. This is listed below:

TOTAL: 1 FAILED, 14300 SUCCESS

1) renders a point
     Scene/Vector3DTilePoints
     Expected to render [255,255,255,255], but actually rendered [254,254,254,255].
    at <Jasmine>
    at packages/engine/Specs/Scene/Vector3DTilePointsSpec.js:177:25 <- Build/Specs/SpecList.js:236887:24

This test was failing on unmodified version of main with the command npm run test. I assume this is "ok" with respect to this issue.

Author checklist

• [x] I have submitted a Contributor License Agreement
• [x] I have added my name to CONTRIBUTORS.md
• [x] I have updated CHANGES.md with a short summary of my change
• [x] I have added or updated unit tests to ensure consistent code coverage
• [x] I have updated the inline documentation, and included code examples where relevant
• [x] I have performed a self-review of my code

[github-actions[bot]]

Thank you for the pull request, @hotpocket!

:white_check_mark: We can confirm we have a CLA on file for you.

[ggetz]

@jjspace Could you please give this a review?

[hotpocket]

@jjspace I believe this is ready.

[hotpocket]

Sorry for any noise this caused in your notifications @hotpocket, we just updated prettier and I was trying to update your branch for you but turned out a little trickier than I thought but that was on my side.

This is finally good to go now

I am comforted to know that I am not the only one that still fights with git :slightly_smiling_face: (xkcd). Thanks @jjspace