### Godot version

v4.0.beta15.official [4fa6edc88]

### System information

Windows 11

### Issue description

When drawing a polygon in the editor, several duplicate vertices are added to the polygon array for each click.  In the image below, I clicked three times to draw the triangle, but got 10 entries.  The number you get varies, though I don't know why; I've seen hundreds of points from drawing a hexagon.  I tested it with a Polygon2D, a CollisionPolygon2D, and a CollisionPolygon3D; the issues occurs with all of them.  It later occurred to me that this might happen with a Curve2D as well, and it does.

![image](https://user-images.githubusercontent.com/2808851/214926182-b8609b87-85a1-4a08-8017-be4eeec912c6.png)


### Steps to reproduce

Add a node that has a Polygon or Curve resource, such as a Polygon2D, draw some points, then check the PackedVector2Array resource.

### Minimal reproduction project

N/A
int original_edited_scene_idx = editor_data.get_edited_scene();
	HashMap<int, List<Node *>> edited_scene_map;
	
	
	for (int i = 0; i < editor_data.get_edited_scene_count(); i++) {
		if (editor_data.get_scene_path(i) != p_instance_path) {
			Node *edited_scene_root = editor_data.get_edited_scene_root(i);
			if (edited_scene_root) {
				List<Node *> valid_nodes;
				find_all_instances_inheriting_path_in_node(edited_scene_root, edited_scene_root, p_instance_path, valid_nodes);
				if (valid_nodes.size() > 0) {
					edited_scene_map[i] = valid_nodes;
				}
			}
		}
	}
	if (edited_scene_map.size() > 0) {
		
		Error err;
		Ref<PackedScene> instance_scene_packed_scene = ResourceLoader::load(p_instance_path, "", ResourceFormatLoader::CACHE_MODE_IGNORE, &err);
		instance_scene_packed_scene->set_path(p_instance_path, true);
		ERR_FAIL_COND(err != OK);
		ERR_FAIL_COND(instance_scene_packed_scene.is_null());
		HashMap<String, Ref<PackedScene>> local_scene_cache;
		local_scene_cache[p_instance_path] = instance_scene_packed_scene;
		for (const KeyValue<int, List<Node *>> &edited_scene_map_elem : edited_scene_map) {