gh-35660: CI Linux: Update platforms
    
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### 📚 Description

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- Adding the newest from `ubuntu`, `linuxmint`, `fedora`, `opensuse`.
- Test a newer 32bit platform.
- Fixing `...-python3.x-minimal` tests broken by #35638.
- A few more parallel jobs because we can.
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### ⌛ Dependencies

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URL: #35660
Reported by: Matthias Köppe
Reviewer(s): Dima Pasechnik, Frédéric Chapoton