Update nbclient requirement from ~=0.8.0 to ~=0.9.0

Updates the requirements on [nbclient](https://github.com/jupyter/nbclient) to permit the latest version.
- [Release notes](https://github.com/jupyter/nbclient/releases)
- [Changelog](https://github.com/jupyter/nbclient/blob/main/CHANGELOG.md)
- [Commits](jupyter/nbclient@v0.8.0...v0.9.0)

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

Signed-off-by: dependabot[bot] <[email protected]>

requirements.txt

@@ -54,7 +54,7 @@ mistune~=3.0.1
 numpy~=1.26.0
 mypy~=1.6.0
 mypy-extensions~=1.0.0
-nbclient~=0.8.0
+nbclient~=0.9.0
 nbsphinx==0.9.1
 nbconvert~=7.11.0
 nbformat~=5.9.0