Remove Web WorldWind support

[leouieda]

It was always kind of flaky and is now broken on the docs and in Jupyter
Lab. We can try better version of this later on. Right now, it's not
easy to test and maintain and shouldn't be in the code base.

Reminders

• Run make format and make check to make sure the code follows the style guide.
• Add tests for new features or tests that would have caught the bug that you're fixing.
• Add new public functions/methods/classes to doc/api/index.rst.
• Write detailed docstrings for all functions/methods.
• If adding new functionality, add an example to docstrings or tutorials.