Bump jupyterlab from 4.2.5 to 4.3.4

Bumps [jupyterlab](/~https://github.com/jupyterlab/jupyterlab) from 4.2.5 to 4.3.4.
- [Release notes](/~https://github.com/jupyterlab/jupyterlab/releases)
- [Changelog](/~https://github.com/jupyterlab/jupyterlab/blob/@jupyterlab/lsp@4.3.4/CHANGELOG.md)
- [Commits](/~https://github.com/jupyterlab/jupyterlab/compare/@jupyterlab/lsp@4.2.5...@jupyterlab/lsp@4.3.4)

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

Signed-off-by: dependabot[bot] <support@github.com>