sway_text_node: Remove duplicate update_source_box call

render_backing_buffer will call update_source_box, no need to do it
twice.

sway/sway_text_node.c

@@ -300,7 +300,6 @@ void sway_text_node_set_max_width(struct sway_text_node *node, int max_width) {
 	buffer->props.max_width = max_width;
 	wlr_scene_buffer_set_dest_size(buffer->buffer_node,
 		get_text_width(&buffer->props), buffer->props.height);
-	update_source_box(buffer);
 	render_backing_buffer(buffer);
 }