Fix ultra long node names

(cherry picked from commit d3f2062d866ca0838549f83cd8870bbde5cda636)

scene/main/node.cpp

@@ -1004,7 +1004,7 @@ void Node::_validate_child_name(Node *p_child, bool p_force_human_readable) {
 
 		bool unique = true;
 
-		if (p_child->data.name == StringName() || p_child->data.name.operator String()[0] == '@') {
+		if (p_child->data.name == StringName()) {
 			//new unique name must be assigned
 			unique = false;
 		} else {