Merge branch '9778-mejorar-logs-en-ejecucion-de-plugins-de-agente' into 'develop', JJOS.

Added log message in case of agent plugin failure

See merge request artica/pandorafms!5507

pandora_agents/unix/pandora_agent

@@ -3749,6 +3749,7 @@ sub module_plugin ($) {
 	
 	# Do not save the output if there was an error
 	if ($? != 0) {
+		log_message ('error', "plugin execution '". $command ."' exited with error code " . $?);
 		return ();
 	}