message: Move finality detector call to separate method.
diff: @@ -405,6 +405,15 @@ where
  let recipient = self.validator_mut(&validator_id)?;
  recipient.push_messages_produced(messages.clone());
  + self.run_finality_detector(&validator_id);
  +
  + Ok(messages)
  + }
  +
  + /// Runs finality detector.
  + fn run_finality_detector(&mut self, validator_id: &ValidatorId) -> Result<(), TestRunError> {
  + let recipient = self.validator_mut(validator_id)?;
  +
  let finality_result = match recipient.consensus.run_finality() {
  FinalityOutcome::Finalized {
  value,
  @@ -430,7 +439,7 @@ where
  recipient.push_finalized(finality_result);
  - Ok(messages)
  + Ok(())
  }
  // Adds vertex to the `recipient` validator state.
  