Bump liger-kernel from 0.4.0 to 0.4.2

Bumps [liger-kernel](https://github.com/linkedin/Liger-Kernel) from 0.4.0 to 0.4.2.
- [Release notes](https://github.com/linkedin/Liger-Kernel/releases)
- [Commits](linkedin/Liger-Kernel@v0.4.0...v0.4.2)

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

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

requirements/notebooks.txt

@@ -1,5 +1,5 @@
 ipython[all] ~=8.30.0
 numpy >=1.23.0,<2  # not yet ready for numpy 2
-liger-kernel == 0.4.0
+liger-kernel == 0.4.2
 cuda-python
 litgpt == 0.5.1