gh-35626: Update the rank function of elliptic curves to use ellrank in pari
### :books: Description
Fixes #35621
Pari has now a very good in-built algorithm to determine the rank and a
set of generators of the Mordell-Weil group of elliptic curves over the
rational. It is, as far as I understand, a port of Denis Simon's script
ellQ.gp. It performs a 2-descent and uses the Cassels Tate pairing to
conclude the rank in many cases - when Sha has no 4-torsion elements.
The functionality to search rational points is also very quick.
### :memo: Checklist
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- `[x]` The title is concise, informative, and self-explanatory.
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- `[x]` I have created tests covering the changes.
- `[x]` I have updated the documentation accordingly.
### :hourglass: Dependencies
- #35614 a pull request that fixes, among other things, the
documentation in the files changed here.
To avoid problems, I based it on that PR.
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URL: https://github.com/sagemath/sage/pull/35626
Reported by: Chris Wuthrich
Reviewer(s): Chris Wuthrich, John Cremona, Lorenz Panny
