message: Use .or_insert_with to make clippy pass
diff: @@ -133,7 +133,7 @@ impl<I: NodeIdT, C: Context> HighwayProtocol<I, C> {
  ) -> Vec<CpResult<I, C>> {
  self.vertices_to_be_added_later
  .entry(future_timestamp)
  - .or_insert(vec![])
  + .or_insert_with(Vec::new)
  .push((sender, pvv));
  vec![ConsensusProtocolResult::ScheduleTimer(future_timestamp)]
  }
  