Bump the actions group across 1 directory with 2 updates

Updates the requirements on [jupyterlab](https://github.com/jupyterlab/jupyterlab) and [notebook](https://github.com/jupyter/notebook) to permit the latest version.

Updates `jupyterlab` 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@4.1.8...@jupyterlab/lsp@4.2.1)

Updates `notebook` to 7.2.0
- [Release notes](https://github.com/jupyter/notebook/releases)
- [Changelog](https://github.com/jupyter/notebook/blob/main/CHANGELOG.md)
- [Commits](https://github.com/jupyter/notebook/compare/@jupyter-notebook/tree@7.1.3...@jupyter-notebook/tree@7.2.0)

---
updated-dependencies:
- dependency-name: jupyterlab
  dependency-type: direct:production
  dependency-group: actions
- dependency-name: notebook
  dependency-type: direct:production
  dependency-group: actions
...

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

demo/requirements.txt

@@ -1,7 +1,7 @@
 # Core modules (mandatory)
 jupyterlite-core==0.3.0
-jupyterlab~=4.1.8
-notebook~=7.1.3
+jupyterlab~=4.2.1
+notebook~=7.2.0
 
 # Python kernel (optional)
 jupyterlite-pyodide-kernel==0.3.1