Enable delivery_error_reports by default

mautrix_signal/example-config.yaml

@@ -205,8 +205,8 @@ bridge:
     # messages.
     # Note that this is not related to Signal delivery receipts.
     delivery_receipts: false
-    # Whether or not delivery errors should be reported as messages in the Matrix room. (not yet implemented)
-    delivery_error_reports: false
+    # Whether or not delivery errors should be reported as messages in the Matrix room.
+    delivery_error_reports: true
     # Whether the bridge should send the message status as a custom com.beeper.message_send_status event.
     message_status_events: false
     # Set this to true to tell the bridge to re-send m.bridge events to all rooms on the next run.