Bump the pip group across 2 directories with 2 updates

Bumps the pip group with 1 update in the /python directory: [idna](https://github.com/kjd/idna).
Bumps the pip group with 1 update in the /template directory: [jupyter-server](https://github.com/jupyter-server/jupyter_server).


Updates `idna` from 3.7 to 3.15
- [Release notes](https://github.com/kjd/idna/releases)
- [Changelog](https://github.com/kjd/idna/blob/master/HISTORY.md)
- [Commits](kjd/idna@v3.7...v3.15)

Updates `jupyter-server` from 2.16.0 to 2.18.0
- [Release notes](https://github.com/jupyter-server/jupyter_server/releases)
- [Changelog](https://github.com/jupyter-server/jupyter_server/blob/main/CHANGELOG.md)
- [Commits](jupyter-server/jupyter_server@v2.16.0...v2.18.0)

---
updated-dependencies:
- dependency-name: idna
  dependency-version: '3.15'
  dependency-type: indirect
  dependency-group: pip
- dependency-name: jupyter-server
  dependency-version: 2.18.0
  dependency-type: direct:production
  dependency-group: pip
...

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Author: dependabot[bot]