message: Also log time it took to gather metrics
diff: @@ -198,9 +198,10 @@ impl MemoryMetrics {
  self.mem_linear_chain.set(linear_chain);
  // Stop the timer explicitly, don't count logging.
  - drop(timer);
  + let duration_s = timer.stop_and_record();
  debug!(%total,
  + %duration_s,
  %net,
  %address_gossiper,
  %storage,
  