Deps: Bump idna in /trigger-workflow in the dependencies group

Bumps the dependencies group in /trigger-workflow with 1 update: [idna](https://github.com/kjd/idna).


Updates `idna` from 3.7 to 3.8
- [Release notes](https://github.com/kjd/idna/releases)
- [Changelog](https://github.com/kjd/idna/blob/master/HISTORY.rst)
- [Commits](kjd/idna@v3.7...v3.8)

---
updated-dependencies:
- dependency-name: idna
  dependency-type: indirect
  update-type: version-update:semver-minor
  dependency-group: dependencies
...

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