fix(udp-server): address Copilot review comments

- Remove unused torrust_tracker_udp_core::self import
- Add missing skill-link marker to issue spec

Author: josecelano

docs/issues/open/1447-change-logging-threshold-connection-id-error.md

@@ -15,6 +15,8 @@ semantic-links:
     - packages/udp-server/src/handlers/error.rs
 ---
 
+<!-- skill-link: create-issue -->
+
 # Issue #1447 - Change the logging threshold for connection ID error to `WARNING`
 
 ## Goal

packages/udp-server/src/handlers/error.rs

@@ -3,9 +3,9 @@ use std::net::SocketAddr;
 use std::ops::Range;
 
 use torrust_net_primitives::service_binding::ServiceBinding;
+use torrust_tracker_udp_core::UDP_TRACKER_LOG_TARGET;
 use torrust_tracker_udp_core::services::announce::UdpAnnounceError;
 use torrust_tracker_udp_core::services::scrape::UdpScrapeError;
-use torrust_tracker_udp_core::{self, UDP_TRACKER_LOG_TARGET};
 use torrust_tracker_udp_protocol::{ErrorResponse, Response, TransactionId};
 use tracing::{Level, instrument};
 use uuid::Uuid;