cu_up: fix test mode

Author: alvasMan

lib/cu_up/cu_up_impl.cpp

@@ -41,7 +41,7 @@ cu_up::cu_up(const cu_up_configuration& config_) : cfg(config_), main_ctrl_loop(
   // Create GTP-U demux
   gtpu_demux_creation_request demux_msg = {};
   demux_msg.cfg.warn_on_drop            = cfg.n3_cfg.warn_on_drop;
-  demux_msg.cfg.test_mode               = true;
+  demux_msg.cfg.test_mode               = cfg.test_mode_cfg.enabled;
   demux_msg.gtpu_pcap                   = cfg.gtpu_pcap;
   ngu_demux                             = create_gtpu_demux(demux_msg);