Might help figuring out where this times out on CI?
We're waiting *20 seconds* for the output to appear, there's no way
that's too slow. So maybe we're going too fast elsewhere?
It's useless - `expect` has a timeout anyway, and it defaults to 5s,
so these 0.5s sleeps just mean it'll always take at least 0.5s.
Sometimes it is useful to let things settle before *sending* text, and
it would be nice to be able to set the timeout for each expect
separately, but just adding to the timeout isn't useful.