Return specific error code when node is not found (#311)

Signed-off-by: ivanpauno <ivanpauno@ekumenlabs.com>

Author: ivanpauno

rmw_fastrtps_shared_cpp/src/rmw_node_info_and_types.cpp

@@ -81,11 +81,12 @@ rmw_ret_t __get_guid_by_name(
         });
 
     if (guid_node_pair == impl->listener->discovered_names.end()) {
-      RCUTILS_LOG_ERROR_NAMED(
-        kLoggerTag,
-        "Unable to find GUID for node: %s", node_name);
-      RMW_SET_ERROR_MSG("Unable to find GUID for node ");
-      return RMW_RET_ERROR;
+      RMW_SET_ERROR_MSG_WITH_FORMAT_STRING(
+        "Node name not found: ns='%s', name='%s",
+        node_namespace,
+        node_name
+      );
+      return RMW_RET_NODE_NAME_NON_EXISTENT;
     }
     guid = guid_node_pair->first;
   }