Bump jupyterlab from 4.1.7 to 4.2.1

Bumps [jupyterlab](https://github.com/jupyterlab/jupyterlab) from 4.1.7 to 4.2.1.
- [Release notes](https://github.com/jupyterlab/jupyterlab/releases)
- [Changelog](https://github.com/jupyterlab/jupyterlab/blob/@jupyterlab/lsp@4.2.1/CHANGELOG.md)
- [Commits](https://github.com/jupyterlab/jupyterlab/compare/@jupyterlab/lsp@4.1.7...@jupyterlab/lsp@4.2.1)

---
updated-dependencies:
- dependency-name: jupyterlab
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]