gh-35170: Fix bug in is_eulerian
### 📚 Description
Fixes #35168.
We set parameter `sort` to `False` when calling `connected_components`.
This fixes the bug as we avoid sorting vertices with different types.
### 📝 Checklist
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### ⌛ Dependencies
None
URL: https://github.com/sagemath/sage/pull/35170
Reported by: David Coudert
Reviewer(s): Marc Mezzarobba
