### 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
slash_idx = parent.rfind("/", slash_idx - 1);
					parent = (slash_idx >= 0 && parent.length() > 1) ? parent.substr(slash_idx + 1) : parent;
					r_filenames.write[set_idx] = parent + r_filenames[set_idx];
				}
			}
			
			bool can_proceed = false;
			RBSet<int>::Element *E = iset.front();
			while (E) {
				String scene_name = r_filenames[E->get()];
				bool duplicate_found = false;
				for (const int &F : iset) {
					if (E->get() == F) {
						continue;
					}
					String other_scene_name = r_filenames[F];
					if (other_scene_name == scene_name) {
						duplicate_found = true;
						break;
					}
				}
				RBSet<int>::Element *to_erase = duplicate_found ? nullptr : E;
				
				
				
				
				
				String path = p_full_paths[E->get()];
				
				scene_name = scene_name.get_basename();