### 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 (p_idx == 0) { 
		current_menu_option = FILE_EXPORT_MESH_LIBRARY;
		if (!editor_data.get_edited_scene_root()) {
			show_accept(TTR("This operation can't be done without a scene."), TTR("OK"));
			return;
		}
		List<String> extensions;
		Ref<MeshLibrary> ml(memnew(MeshLibrary));
		ResourceSaver::get_recognized_extensions(ml, &extensions);
		file_export_lib->clear_filters();
		for (const String &E : extensions) {
			file_export_lib->add_filter("*." + E);
		}
		file_export_lib->popup_file_dialog();
		file_export_lib->set_title(TTR("Export Mesh Library"));
	} else { 
		if (export_as_menu->get_item_submenu(p_idx).is_empty()) { 
			Callable callback = export_as_menu->get_item_metadata(p_idx);
			Callable::CallError ce;
			Variant result;
			callback.callp(nullptr, 0, result, ce);
			if (ce.error != Callable::CallError::CALL_OK) {
				String err = Variant::get_callable_error_text(callback, nullptr, 0, ce);
				ERR_PRINT("Error calling function from export_as menu: " + err);
			}
		}
	}
}
int EditorNode::_next_unsaved_scene(bool p_valid_filename, int p_start) {