### 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
if (!editor_data.get_edited_scene_root() && editor_data.get_edited_scene_count() == 2) {
		_remove_edited_scene();
	} else if (!p_silent_change_tab) {
		_scene_tab_changed(idx);
	} else {
		set_current_scene(idx);
	}
	dependency_errors.clear();
	Error err;
	Ref<PackedScene> sdata = ResourceLoader::load(lpath, "", ResourceFormatLoader::CACHE_MODE_REPLACE, &err);
	if (!sdata.is_valid()) {
		_dialog_display_load_error(lpath, err);
		opening_prev = false;
		if (prev != -1) {
			set_current_scene(prev);
			editor_data.remove_scene(idx);
		}
		return ERR_FILE_NOT_FOUND;
	}
	if (!p_ignore_broken_deps && dependency_errors.has(lpath)) {
		current_menu_option = -1;
		Vector<String> errors;
		for (const String &E : dependency_errors[lpath]) {
			errors.push_back(E);
		}
		dependency_error->show(DependencyErrorDialog::MODE_SCENE, lpath, errors);
		opening_prev = false;
		if (prev != -1) {
			set_current_scene(prev);
			editor_data.remove_scene(idx);