### 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
Ref<ResourceImporterTexture> import_texture;
		import_texture.instantiate();
		ResourceFormatImporter::get_singleton()->add_importer(import_texture);
		Ref<ResourceImporterLayeredTexture> import_cubemap;
		import_cubemap.instantiate();
		import_cubemap->set_mode(ResourceImporterLayeredTexture::MODE_CUBEMAP);
		ResourceFormatImporter::get_singleton()->add_importer(import_cubemap);
		Ref<ResourceImporterLayeredTexture> import_array;
		import_array.instantiate();
		import_array->set_mode(ResourceImporterLayeredTexture::MODE_2D_ARRAY);
		ResourceFormatImporter::get_singleton()->add_importer(import_array);
		Ref<ResourceImporterLayeredTexture> import_cubemap_array;
		import_cubemap_array.instantiate();
		import_cubemap_array->set_mode(ResourceImporterLayeredTexture::MODE_CUBEMAP_ARRAY);
		ResourceFormatImporter::get_singleton()->add_importer(import_cubemap_array);
		Ref<ResourceImporterLayeredTexture> import_3d;
		import_3d.instantiate();
		import_3d->set_mode(ResourceImporterLayeredTexture::MODE_3D);
		ResourceFormatImporter::get_singleton()->add_importer(import_3d);
		Ref<ResourceImporterImage> import_image;
		import_image.instantiate();
		ResourceFormatImporter::get_singleton()->add_importer(import_image);
		Ref<ResourceImporterTextureAtlas> import_texture_atlas;
		import_texture_atlas.instantiate();
		ResourceFormatImporter::get_singleton()->add_importer(import_texture_atlas);
		Ref<ResourceImporterDynamicFont> import_font_data_dynamic;
		import_font_data_dynamic.instantiate();
		ResourceFormatImporter::get_singleton()->add_importer(import_font_data_dynamic);
		Ref<ResourceImporterBMFont> import_font_data_bmfont;
		import_font_data_bmfont.instantiate();