if "greatest" is selected, second coordinate should be picked

[mmagician]

Description

If I'm not mistaken, then according to the docs and code of get_ys_from_x_unchecked, the second value should be selected if greatest flag is true.

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[Pratyush]

Thanks for the fix, it is indeed inconsistent with the documentation. Could you check against the call sites to see if this fix works? I'm asking because the code recently changed.

[mmagician]

It's only used in sample and get_random_bytes. These methods didn't care for anything specific regarding the y-coordinate, as long as it was a valid point - which it is, no matter which coordinate is picked.