Remove the javascript folder

[markhallen]

What are you trying to accomplish?

Tidy up the repository by removing the javascript folder after the pivot to #11559

Anything you want to highlight for special attention from reviewers?

The removal should be relatively clean as all code is contained in the javascript folder. We also removed the related issue labeler config and the sorbet exclusion for javascript/spec.

How will you know you've accomplished your goal?

Everything should still work as it was except dry run with javascript.

Checklist

• I have run the complete test suite to ensure all tests and linters pass.
• I have thoroughly tested my code changes to ensure they work as expected, including adding additional tests for new functionality.
• I have written clear and descriptive commit messages.
• I have provided a detailed description of the changes in the pull request, including the problem it addresses, how it fixes the problem, and any relevant details about the implementation.
• I have ensured that the code is well-documented and easy to understand.