message: Added tracing to track depth of finalized block
diff: @@ -72,6 +72,10 @@ impl<C: Context> FinalityDetector<C> {
  None
  };
  + trace!(
  + %block.height,
  + "Depth of the last finalized block"
  + );
  Some(FinalizedBlock {
  value: block.value.clone(),
  timestamp: vote.timestamp,
  