Bump jupyterlab from 3.6.7 to 3.6.8

Bumps [jupyterlab](https://github.com/jupyterlab/jupyterlab) from 3.6.7 to 3.6.8.
- [Release notes](https://github.com/jupyterlab/jupyterlab/releases)
- [Changelog](https://github.com/jupyterlab/jupyterlab/blob/main/CHANGELOG.md)
- [Commits](https://github.com/jupyterlab/jupyterlab/compare/@jupyterlab/vdom@3.6.7...@jupyterlab/vdom@3.6.8)

---
updated-dependencies:
- dependency-name: jupyterlab
  dependency-type: direct:production
...

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

requirements.txt

@@ -57,7 +57,7 @@ jupyter_client==7.4.9
 jupyter_core==5.1.5
 jupyter_server==2.1.0
 jupyter_server_terminals==0.4.4
-jupyterlab==3.6.7
+jupyterlab==3.6.8
 jupyterlab_git==0.50.0
 jupyterlab-lsp==3.10.2
 jupyterlab-pygments==0.2.2