Retrying the passwd command several times inside "gpg --card-edit" consistently
fails no matter what I do before.
However, using "gpg --change-pin" only fails at most once in a row: the first
time it fails with general after the first key press, then retrying to change
the password succeeds, and subsequent changes succeed immediately and consistently.
But, if I cancel a pin entry, then I have a single failure, then it works (with
--change-pin).
Maybe some kind of buffer isn't flushed somewhere, and the first tries clears
it, but passwd in --card-edit doesn't...