sagemathgh-38390: simplify some iterations (ruff PERF102)

    
this is simplifying some iterations, and was scripted using `ruff`

### 📝 Checklist

- [x] The title is concise and informative.
- [x] The description explains in detail what this PR is about.
    
URL: sagemath#38390
Reported by: Frédéric Chapoton
Reviewer(s): David Coudert