Bump ipykernel from 6.21.1 to 6.21.2

Bumps [ipykernel](https://github.com/ipython/ipykernel) from 6.21.1 to 6.21.2.
- [Release notes](https://github.com/ipython/ipykernel/releases)
- [Changelog](https://github.com/ipython/ipykernel/blob/main/CHANGELOG.md)
- [Commits](ipython/ipykernel@v6.21.1...v6.21.2)

---
updated-dependencies:
- dependency-name: ipykernel
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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