gh-36377: clean one test file
    
This is cleaning the modified file for full pep8 compliance.

### 📝 Checklist

- [x] The title is concise, informative, and self-explanatory.
- [x] The description explains in detail what this PR is about.
    
URL: #36377
Reported by: Frédéric Chapoton
Reviewer(s): David Coudert

Author: Release Manager