### Godot version

4.0 dev_build

### System information

Ubuntu 22.04.1

### Issue description

The "Lookup Symbol" button don't appears for custorm class names.
Related issues: #68475,  #73167.
I tried apply #68311, #69473 and #73196. It don't helps.
The `Ctrl+LMB` works right for all cases.

### Steps to reproduce

Right click to the `CustomClassA` symbol in the `custom_class_b.gd` anywhere. The `Lookup Symbol` button don't appears in the context menu.

### Minimal reproduction project

Example from  #68475.
if (get_parent_control()) {
		String icon_name = script->get_class();
		if (script->is_built_in()) {
			icon_name += "Internal";
		}
		if (get_parent_control()->has_theme_icon(icon_name, SNAME("EditorIcons"))) {
			return get_parent_control()->get_theme_icon(icon_name, SNAME("EditorIcons"));
		} else if (get_parent_control()->has_theme_icon(script->get_class(), SNAME("EditorIcons"))) {
			return get_parent_control()->get_theme_icon(script->get_class(), SNAME("EditorIcons"));
		}
	}
	return Ref<Texture2D>();
}
void ScriptTextEditor::_validate_script() {