### Godot version

4.1.beta (7b1387ff2)

### System information

Mageia 9, Linux

### Issue description

When opening an empty project in latest `master`, I get these errors:
```
ERROR: Index p_idx = -1 is out of bounds (edited_scene.size() = 1).
   at: get_scene_path (editor/scu/../editor_data.cpp:880)
ERROR: Index p_idx = -1 is out of bounds (edited_scene.size() = 1).
   at: check_and_update_scene (editor/scu/../editor_data.cpp:683)
ERROR: Index p_idx = -1 is out of bounds (edited_scene.size() = 1).
   at: set_edited_scene (editor/scu/../editor_data.cpp:745)
```

Possibly related to recent changes to restore past sessions, but there's nothing to restore in this case?

### Steps to reproduce

- Create a new project, edit it
- Quit to project manager
- Re-open the newly created project -> errors

### Minimal reproduction project

Empty project.
tab_preview_panel->hide();
	if (p_tab == editor_data.get_edited_scene()) {
		return; 
	}
	set_current_scene(p_tab);
}
Button *EditorNode::add_bottom_panel_item(String p_text, Control *p_item) {
	Button *tb = memnew(Button);
	tb->set_flat(true);
	tb->connect("toggled", callable_mp(this, &EditorNode::_bottom_panel_switch).bind(bottom_panel_items.size()));
	tb->set_text(p_text);
	tb->set_toggle_mode(true);
	tb->set_focus_mode(Control::FOCUS_NONE);
	bottom_panel_vb->add_child(p_item);
	bottom_panel_hb->move_to_front();
	bottom_panel_hb_editors->add_child(tb);
	p_item->set_v_size_flags(Control::SIZE_EXPAND_FILL);
	p_item->hide();
	BottomPanelItem bpi;
	bpi.button = tb;
	bpi.control = p_item;
	bpi.name = p_text;
	bottom_panel_items.push_back(bpi);
	return tb;
}
void EditorNode::hide_bottom_panel() {