message: Update `mk_span` doc comment
diff: @@ -213,10 +213,11 @@ where
  /// Creates a logging span for a specific connection.
  #[inline]
  fn mk_span(&self, addr: SocketAddr) -> Span {
  - // Note: The jury is still out on whether we want to create a single span and cache it, or
  - // create a new one each time this is called. The advantage of the former is external tools
  - // have it easier correlating all related information, while the drawback is not being able
  - // to change the parent span link, which might be awkward.
  + // Note: The jury is still out on whether we want to create a single span per connection and
  + // cache it, or create a new one (with the same connection ID) each time this is called. The
  + // advantage of the former is external tools have it easier correlating all related
  + // information, while the drawback is not being able to change the parent span link, which
  + // might be awkward.
  if let Some(_outgoing) = self.outgoing.get(&addr) {
  error_span!("outgoing", %addr, state = "TODO")
  