### 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
left_l_vsplit->hide();
	right_r_vsplit->hide();
	
	left_r_hsplit->set_split_offset(270 * EDSCALE);
	main_hsplit->set_split_offset(-270 * EDSCALE);
	
	const String docks_section = "docks";
	default_layout.instantiate();
	
	default_layout->set_value(docks_section, "dock_3", "Scene,Import");
	default_layout->set_value(docks_section, "dock_4", "FileSystem");
	default_layout->set_value(docks_section, "dock_5", "Inspector,Node,History");
	for (int i = 0; i < vsplits.size(); i++) {
		default_layout->set_value(docks_section, "dock_split_" + itos(i + 1), 0);
	}
	default_layout->set_value(docks_section, "dock_hsplit_1", 0);
	default_layout->set_value(docks_section, "dock_hsplit_2", 270 * EDSCALE);
	default_layout->set_value(docks_section, "dock_hsplit_3", -270 * EDSCALE);
	default_layout->set_value(docks_section, "dock_hsplit_4", 0);
	_update_layouts_menu();
	
	bottom_panel = memnew(PanelContainer);
	bottom_panel->add_theme_style_override("panel", gui_base->get_theme_stylebox(SNAME("BottomPanel"), SNAME("EditorStyles")));
	center_split->add_child(bottom_panel);
	center_split->set_dragger_visibility(SplitContainer::DRAGGER_HIDDEN);
	bottom_panel_vb = memnew(VBoxContainer);
	bottom_panel->add_child(bottom_panel_vb);
	bottom_panel_hb = memnew(HBoxContainer);
	bottom_panel_hb->set_custom_minimum_size(Size2(0, 24 * EDSCALE)); 
	bottom_panel_vb->add_child(bottom_panel_hb);