message: Test detecting if FTT is exceeded.
diff: @@ -423,6 +423,7 @@ fn simple_consensus_faults() {
  let alice_kp = Keypair::from(ALICE_SECRET_KEY.clone());
  let bob_kp = Keypair::from(BOB_SECRET_KEY.clone());
  + let carol_kp = Keypair::from(CAROL_SECRET_KEY.clone());
  let sender = *ALICE_NODE_ID;
  let timestamp = Timestamp::now();
  @@ -468,6 +469,15 @@ fn simple_consensus_faults() {
  let msg = create_message(&validators, 3, vote(false), &bob_kp);
  let outcomes = sc.handle_message(&mut rng, sender, msg, timestamp);
  expect_finalized(&outcomes, &[(&proposal1, 0), (&proposal2, 1)]);
  +
  + // Now Carol starts two nodes by mistake, and equivocates. That crosses the FTT.
  + let msg = create_message(&validators, 3, vote(true), &carol_kp);
  + expect_no_gossip_block_finalized(sc.handle_message(&mut rng, sender, msg, timestamp));
  + let msg = create_message(&validators, 3, vote(false), &carol_kp);
  + let outcomes = sc.handle_message(&mut rng, sender, msg, timestamp);
  + assert!(outcomes
  + .iter()
  + .any(|outcome| { matches!(outcome, ProtocolOutcome::FttExceeded) }));
  }
  #[test]
  