[DEPENDABOT]: Bump nbconvert from 6.5.4 to 7.16.4 in /docs

Bumps [nbconvert](https://github.com/jupyter/nbconvert) from 6.5.4 to 7.16.4.
- [Release notes](https://github.com/jupyter/nbconvert/releases)
- [Changelog](https://github.com/jupyter/nbconvert/blob/main/CHANGELOG.md)
- [Commits](https://github.com/jupyter/nbconvert/commits/v7.16.4)

---
updated-dependencies:
- dependency-name: nbconvert
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

requirements.txt

@@ -59,7 +59,7 @@ mdurl==0.1.2
 mistune==0.8.4
 natsort==8.4.0
 nbclient==0.10.0
-nbconvert==6.5.4
+nbconvert==7.16.4
 nbformat==5.10.3
 networkx==3.2.1
 nox-poetry==1.0.3