### Godot version

v4.1.1.stable.official [bd6af8e0e]

### System information

v4.1.1.stable.official [bd6af8e0e]

### Issue description

In-script documentation (`##`) for `signal` members is not appearing in the _Node_ tab as expected.  Other documentation appears to work correctly in the _Inspector_ tab.

Working example (exported variable):
![GodotDocumentationWorking](https://github.com/godotengine/godot/assets/13528480/ab9b19d4-c9f7-4658-8379-f2c2699310b8)

Non-working example (`signal`)
![GodotDocumentationNotWorking](https://github.com/godotengine/godot/assets/13528480/06824f6a-b135-4454-a06e-7c6feb34060b)

I have tried deselecting and reselecting the associated Node, changing between the tabs on the left pane, changing active scripts and even restarting Godot - nothing makes it work.  According to the [GScript Documentation on Documentation Comments](https://docs.godotengine.org/en/stable/tutorials/scripting/gdscript/gdscript_documentation_comments.html), this **should** work, right?  Or is there something completely obvious that I am missing?


### Steps to reproduce

1. In Godot, create a new Node of type `Node`
2. Attach a new script to this Node, accepting all current defaults
3. In the script editor create a `signal` called `Foo` and right above it, create a `##` comment for it
4. Also create an `@export`ed integer variable called `Bar` and also create a `##` comment for it
5. Unselect and reselect the Node in the _Scene_ tab to refresh the _Inspector_ and _Node_ tabs
6. Hover over the variable in the _Inspector_ tab and see that the added description is shown correctly
7. Hover over the signal in the _Node_ tab and see that the added description is **not** shown and "_No description._" is shown instead

This is an example of the script that could be added:
```
## This is signal foo!
signal Foo

## This is exported signal bar!
@export var Bar : int = 0
```

### Minimal reproduction project

N/A
TreeItem *signal_item = p_item.get_parent();
	ERR_FAIL_COND(!signal_item);
	Connection connection = p_item.get_metadata(0);
	ConnectDialog::ConnectionData cd = connection;
	Node *src = Object::cast_to<Node>(cd.source);
	Node *dst = Object::cast_to<Node>(cd.target);
	if (src && dst) {
		const String &signal_name_ref = cd.signal;
		PackedStringArray signal_args = signal_item->get_metadata(0).operator Dictionary()["args"];
		connect_dialog->set_title(vformat(TTR("Edit Connection: '%s'"), cd.signal));
		connect_dialog->popup_dialog(signal_name_ref);
		connect_dialog->init(cd, signal_args, true);
	}
}
/*
 * Open slot method location in script editor.
 */
void ConnectionsDock::_go_to_script(TreeItem &p_item) {