Not sure about when we stopped needing them, but all usages of
require_dependency definitely become obsolete after we started using
Zeitwerk in commit 5f24ee912.
We're also going to rename `Poll::Question::Answer` to
`Poll::Question::Option`, so the conflict of having two `Answer`
classes, that made us add this code in the first place, will not even
exist.
5a0fa28189