gh-38518: CI Linux: Consolidate jobs
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Thanks to the more powerful runners in use since early 2024, we can do
away with the splits between
- `standard-pre` and `standard`
- `minimal-pre` and `minimal`
- `optional-0-o` and `optional-p-z`
- `experimental-0-o` and `experimental-p-z`
This makes the CI runs a bit easier to navigate for those who look at
them.
- Test run: https://github.com/mkoeppe/sage/actions/runs/10438362191
This should also fix "No space left on device" aborts as seen for
example in https://github.com/mkoeppe/sage/actions/runs/10426436105 for
standard-pre (where we did not use to maximize the available disk
space).
### :memo: Checklist
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preview.
### :hourglass: Dependencies
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- Depends on #37434 (merged here)
URL: https://github.com/sagemath/sage/pull/38518
Reported by: Matthias Köppe
Reviewer(s): Kwankyu Lee, Matthias Köppe
