regress/key-options.sh: should expire much later than in 2038

[Alexander Kanavin]

Hello,

Testing systems for Y2038 safety is done by setting the clock to after
2038, and then running all available test suites. This however
requires that actual Y2038 issues are not masked by key expiry errors
(when tests hardcode expiry dates), and this is what happens in this
particular test.

I've submitted a fix here:
https://github.com/openssh/openssh-portable/pull/425
and here:
https://bugzilla.mindrot.org/show_bug.cgi?id=3684

but no one's reacting so I thought I try this channel as well.

Thanks,
Alex