### Godot version

4.1.dev (dc625bcbfc5b587ba8867481ee7a1f6a567c25d0)

### System information

Mageia 9, Linux

### Issue description

When importing a project in current `master`, the following error is raised for each asset that gets imported:
```
Attempting to parent and popup a dialog that already has a parent.
```

It seems to be raised once per asset, caused by the progress dialog.

CC @bruvzg

### Steps to reproduce

- Import a new project in Godot that contains importable assets, e.g. https://github.com/RPicster/godot4-demo-desert-light

### Minimal reproduction project

See above.
MessageQueue::get_singleton()->push_call(this, "_end_task", p_task);
}
ProgressDialog *ProgressDialog::singleton = nullptr;
void ProgressDialog::_notification(int p_what) {
	if (p_what == NOTIFICATION_VISIBILITY_CHANGED) {
		if (!is_visible()) {
			Node *p = get_parent();
			if (p) {
				p->remove_child(this);
			}
		}
	}
}
void ProgressDialog::_popup() {
	Size2 ms = main->get_combined_minimum_size();
	ms.width = MAX(500 * EDSCALE, ms.width);
	Ref<StyleBox> style = main->get_theme_stylebox(SNAME("panel"), SNAME("PopupMenu"));
	ms += style->get_minimum_size();
	main->set_offset(SIDE_LEFT, style->get_margin(SIDE_LEFT));
	main->set_offset(SIDE_RIGHT, -style->get_margin(SIDE_RIGHT));
	main->set_offset(SIDE_TOP, style->get_margin(SIDE_TOP));
	main->set_offset(SIDE_BOTTOM, -style->get_margin(SIDE_BOTTOM));
	EditorInterface::get_singleton()->popup_dialog_centered(this, ms);
}
void ProgressDialog::add_task(const String &p_task, const String &p_label, int p_steps, bool p_can_cancel) {