Stop the sync server quietly when Pelican sends Ctrl+C.

sync/pitlog_sync.py

@@ -451,7 +451,12 @@ def serve():
     print(f"Pit Log sync listening on {port}", flush=True)
     print("Each car in the app has its own token.", flush=True)
     server = ThreadingHTTPServer(("0.0.0.0", port), Handler)
+    try:
         server.serve_forever()
+    except KeyboardInterrupt:
+        print("Pit Log sync stopped.", flush=True)
+    finally:
+        server.server_close()
 
 
 def selftest():