### 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
canvas_item_mat_convert.instantiate();
		resource_conversion_plugins.push_back(canvas_item_mat_convert);
		Ref<ParticleProcessMaterialConversionPlugin> particles_mat_convert;
		particles_mat_convert.instantiate();
		resource_conversion_plugins.push_back(particles_mat_convert);
		Ref<ProceduralSkyMaterialConversionPlugin> procedural_sky_mat_convert;
		procedural_sky_mat_convert.instantiate();
		resource_conversion_plugins.push_back(procedural_sky_mat_convert);
		Ref<PanoramaSkyMaterialConversionPlugin> panorama_sky_mat_convert;
		panorama_sky_mat_convert.instantiate();
		resource_conversion_plugins.push_back(panorama_sky_mat_convert);
		Ref<PhysicalSkyMaterialConversionPlugin> physical_sky_mat_convert;
		physical_sky_mat_convert.instantiate();
		resource_conversion_plugins.push_back(physical_sky_mat_convert);
		Ref<FogMaterialConversionPlugin> fog_mat_convert;
		fog_mat_convert.instantiate();
		resource_conversion_plugins.push_back(fog_mat_convert);
		Ref<VisualShaderConversionPlugin> vshader_convert;
		vshader_convert.instantiate();
		resource_conversion_plugins.push_back(vshader_convert);
	}
	update_spinner_step_msec = OS::get_singleton()->get_ticks_msec();
	update_spinner_step_frame = Engine::get_singleton()->get_frames_drawn();
	editor_plugin_screen = nullptr;
	editor_plugins_over = memnew(EditorPluginList);
	editor_plugins_force_over = memnew(EditorPluginList);
	editor_plugins_force_input_forwarding = memnew(EditorPluginList);
	Ref<GDExtensionExportPlugin> gdextension_export_plugin;
	gdextension_export_plugin.instantiate();
	EditorExport::get_singleton()->add_export_plugin(gdextension_export_plugin);