⬆️ Bump notebook from 7.2.0 to 7.2.2 in /lib/walden (#3215)

Bumps [notebook](https://github.com/jupyter/notebook) from 7.2.0 to 7.2.2.
- [Release notes](https://github.com/jupyter/notebook/releases)
- [Changelog](https://github.com/jupyter/notebook/blob/@jupyter-notebook/[email protected]/CHANGELOG.md)
- [Commits](https://github.com/jupyter/notebook/compare/@jupyter-notebook/[email protected]...@jupyter-notebook/[email protected])

---
updated-dependencies:
- dependency-name: notebook
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: lucasrodes <[email protected]>