build(deps): bump nbconvert from 7.0.0 to 7.1.0 in /mpcontribs-portal

Bumps [nbconvert](https://github.com/jupyter/nbconvert) from 7.0.0 to 7.1.0.
- [Release notes](https://github.com/jupyter/nbconvert/releases)
- [Commits](jupyter/nbconvert@7.0.0...7.1.0)

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

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

mpcontribs-portal/requirements.txt

@@ -13,7 +13,7 @@ jinja2==3.1.2
 json2html==1.3.0
 monty==2022.9.9
 mpcontribs-client==4.4.7
-nbconvert==7.0.0
+nbconvert==7.1.0
 nbformat==5.6.1
 redis==4.3.4
 scipy==1.9.1