refactor: remove obsolete license table preservation

tenant-service/src/main/java/com/xuqm/tenant/service/SystemUpdateService.java

@@ -401,7 +401,6 @@ public class SystemUpdateService {
         PRESERVE_TABLES.put("t_app",                "id");
         PRESERVE_TABLES.put("t_feature_service",    "id");
         PRESERVE_TABLES.put("t_risk_config",        "id");
-        PRESERVE_TABLES.put("app_licenses",         "app_key");
         PRESERVE_TABLES.put("t_sensitive_word",             "id");
         PRESERVE_TABLES.put("t_operation_log",             "id");
         PRESERVE_TABLES.put("t_service_activation_request","id");