Code based on urlgetter had this event and we would like to have this
event with step-by-step code as well.
Because there's no tracing for HTTP when using step-by-step, we will
need to include emitting these events inside the boilerplate.
By doing that, we emit events out of order, so make sure we sort
them by T, which is "the moment when the event was collected".
Part of https://github.com/ooni/probe/issues/2238
