### Godot version

v4.0.beta.custom_build [fab9926a9]

### System information

Fedora 37

### Issue description

When creating a new inherited scene, saving the scene (for example with Ctrl+S) defaults to overwriting the scene being inherited, instead of prompting for a location to save to.

### Steps to reproduce

1. Create a new inherited scene
2. Press Ctrl+S

If the scene being inherited is imported (for example from a glTF), an error displays. If the inherited scene is a .tscn or .scn, it gets overridden by an inherited scene that tries to inherit itself, which is impossible and thus corrupt.

### Minimal reproduction project

N/A
Control *dock = dock_slot[dock_popup_selected_idx]->get_current_tab_control();
	ERR_FAIL_COND(!dock);
	Size2 borders = Size2(4, 4) * EDSCALE;
	
	Size2 dock_size = dock->get_size() + borders * 2;
	Point2 dock_screen_pos = dock->get_global_position() + get_tree()->get_root()->get_position() - borders;
	int dock_index = dock->get_index();
	dock_slot[dock_popup_selected_idx]->remove_child(dock);
	Window *window = memnew(Window);
	window->set_title(TTRGET(dock->get_name()));
	Panel *p = memnew(Panel);
	p->add_theme_style_override("panel", gui_base->get_theme_stylebox(SNAME("PanelForeground"), SNAME("EditorStyles")));
	p->set_anchors_and_offsets_preset(Control::PRESET_FULL_RECT);
	window->add_child(p);
	MarginContainer *margin = memnew(MarginContainer);
	margin->set_anchors_and_offsets_preset(Control::PRESET_FULL_RECT);
	margin->add_theme_constant_override("margin_right", borders.width);
	margin->add_theme_constant_override("margin_top", borders.height);
	margin->add_theme_constant_override("margin_left", borders.width);
	margin->add_theme_constant_override("margin_bottom", borders.height);
	window->add_child(margin);
	dock->set_anchors_and_offsets_preset(Control::PRESET_FULL_RECT);
	margin->add_child(dock);
	window->set_wrap_controls(true);
	window->set_size(dock_size);
	window->set_position(dock_screen_pos);
	window->set_transient(true);
	window->connect("close_requested", callable_mp(this, &EditorNode::_dock_floating_close_request).bind(dock));
	window->set_meta("dock_slot", dock_popup_selected_idx);
	window->set_meta("dock_index", dock_index);