add jupyterlite-javascript-kernel 0.3.0

[bollwyvl]

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[conda-forge-webservices]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipes/jupyterlite-javascript-kernel) and found it was in an excellent condition.

[bollwyvl]

@conda-forge/help-python ready for review

[bollwyvl]

Thanks!