Update TtdMauiPageEventHandler.cs

Author: aritchie

src/Sentry.Maui/Internal/TtdMauiPageEventHandler.cs

@@ -61,6 +61,7 @@ public async void OnAppearing(Page page)
             using var cts = new CancellationTokenSource();
             cts.CancelAfterSafe(TimeSpan.FromSeconds(30));
 
+            // TODO: grab last span and add ttfd measurement
             // we're assuming that the user starts any spans around data calls, we wait for those before marking the transaction as finished
             await _transaction.FinishWithLastSpanAsync(cts.Token).ConfigureAwait(false);
         }