Fix terrain listener memory leak when removing Marker

[rczobor]

A memory leak is caused when adding and removing markers. .on('terrain', this._update) event listener is added when Marker's addTo is called, but off call is missing from the remove method.

Launch Checklist

• Confirm your changes do not include backports from Mapbox projects (unless with compliant license) - if you are not sure about this, please ask!
• Briefly describe the changes in this PR.
• Link to related issues.
• Include before/after visuals or gifs if this PR includes visual changes.
• Write tests for all new functionality.
• Document any changes to public APIs.
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• Add an entry to CHANGELOG.md under the ## main section.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 87.68%. Comparing base (917fbb8) to head (5da6b3e).
Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4284      +/-   ##
==========================================
+ Coverage   87.42%   87.68%   +0.26%     
==========================================
  Files         242      242              
  Lines       33081    33082       +1     
  Branches     2170     2184      +14     
==========================================
+ Hits        28920    29009      +89     
+ Misses       3176     3075     -101     
- Partials      985      998      +13     

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[TimMcCauley]

Thank you @rczobor this is a really nice find which will help us in our project, too.

[HarelM]

THANKS!

[HarelM]

Did you happen to check if there are other event that are causing a leak in this class?
I think there are in the geolocation control, but this control doesn't get added and removed often...

[rczobor]

Thanks!

We didn't notice any other events so far, only this one. We do use supercluster to render thousands of dynamic markers with click/drag event handlers on the map via react-nap-gl, and this one popped out. It can crash a tab in minutes when abused.