Stop marker from flashing on initial load if it's occluded by the globe

[Eldemarkki]

This pull request fixes issue #13000. See this video for a demonstration of the bug:

bug.mp4

Here is the same example, after the fix:

fixed.mp4

Here is a possibly relevant conversation from when the throttling was initially added in 2021: #10564 (comment). I didn't notice any performance issues when testing the fix, but maybe someone more experienced can tell if this fix causes problems somewhere.

I tested also with adding an isInitialLoad boolean to Marker's _update function so that we could keep the _fadeTimer. It caused problems with popups flashing on initial load, but I managed to fix them. That solution was less clean than this one in my opinion, but I think it's still a possibility if we want to keep the fade timer.

This is my first PR to Mapbox, please tell me if there is something that I did incorrectly or that I should still fix, I'm open to all feedback! :)

Launch Checklist

• Make sure the PR title is descriptive and preferably reflects the change from the user's perspective.
• Add additional detail and context in the PR description (with screenshots/videos if there are visual changes).
• Manually test the debug page.
• Write tests for all new functionality and make sure the CI checks pass.
• Document any changes to public APIs.
• Post benchmark scores if the change could affect performance.
• Tag @mapbox/map-design-team @mapbox/static-apis if this PR includes style spec API or visual changes.
• Tag @mapbox/gl-native if this PR includes shader changes or needs a native port.

[CLAassistant]

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[ibesora]

Unfortunately we can't accept this PR since it removes some functionality. The fade timer this removes is used to hide markers when they are occluded.
I know it's been really long since you opened this but @Eldemarkki are you willing to improve this? Otherwise I'll close this PR and work on this internally.
Thanks for the work, and sorry for replying so late.

[Eldemarkki]

I'll close it, thanks!