### 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
Node *valid_source_owner = nullptr;
			if (source_node) {
				valid_source_owner = source_node->get_owner();
				while (valid_source_owner) {
					if (valid_source_owner == p_root) {
						break;
					}
					valid_source_owner = valid_source_owner->get_owner();
				}
			}
			if (!source_node || valid_source_owner == nullptr) {
				
				if (!c.callable.is_custom()) {
					valid_connections_from.push_back(c);
				}
			}
		}
		
		List<Node::GroupInfo> groups;
		p_node->get_groups(&groups);
		if (!modified_properties.is_empty() || !valid_connections_to.is_empty() || !valid_connections_from.is_empty() || !groups.is_empty()) {
			ModificationNodeEntry modification_node_entry;
			modification_node_entry.property_table = modified_properties;
			modification_node_entry.connections_to = valid_connections_to;
			modification_node_entry.connections_from = valid_connections_from;
			modification_node_entry.groups = groups;
			p_modification_table[p_root->get_path_to(p_node)] = modification_node_entry;
		}
	} else {
		AdditiveNodeEntry new_additive_node_entry;