Random failure in schemes/elliptic_curves/gp_simon.py

[collares]

I've been seeing this for a while now (and others have as well), but I couldn't find an issue for it. Tested with Sage 10.6 on x86_64 and Pari 2.17.2.

sage -t --long --warn-long 30.0 --random-seed=143717418435003165899331009016503249096 /nix/store/55s2wvhzagih5yr8nzx0ggghpmi0myi3-sage-src-10.6/src/sage/schemes/elliptic_curves/gp_simon.py
**********************************************************************
File "/nix/store/55s2wvhzagih5yr8nzx0ggghpmi0myi3-sage-src-10.6/src/sage/schemes/elliptic_curves/gp_simon.py", line 84, in sage.schemes.elliptic_curves.gp_simon.?
Failed example:
    E.simon_two_descent()                             # long time
Expected:
    (0, 2, [])
Got:
    (2, 2, [(-121/64*w - 2719/64 : -15555/512*w - 186181/512 : 1)])
**********************************************************************
1 item had failures:
   1 of  17 in sage.schemes.elliptic_curves.gp_simon.?
    [16 tests, 1 failure, 13.28s wall]

[fchapoton]

related to comments in #38461