### 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
editor_data.move_edited_scene_to_index(idx_to);
	_update_scene_tabs();
}
void EditorNode::_thumbnail_done(const String &p_path, const Ref<Texture2D> &p_preview, const Ref<Texture2D> &p_small_preview, const Variant &p_udata) {
	int p_tab = p_udata.operator signed int();
	if (p_preview.is_valid()) {
		Rect2 rect = scene_tabs->get_tab_rect(p_tab);
		rect.position += scene_tabs->get_global_position();
		tab_preview->set_texture(p_preview);
		tab_preview_panel->set_position(rect.position + Vector2(0, rect.size.height));
		tab_preview_panel->show();
	}
}
void EditorNode::_scene_tab_changed(int p_tab) {