### Godot version

master

### System information

Godot v4.2.beta (0ea75d77c) - Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 2070 (NVIDIA; 31.0.15.3598) - Intel(R) Core(TM) i7-10750H CPU @ 2.60GHz (12 Threads)

### Issue description

When any of the Import, Filesystem, Node, or History docks are floating, changing an editor feature crashes the engine.
Changing any setting or selecting a different profile triggers it.

This is because `EditorNode::_feature_profile_changed` assumes the docks are in a `TabContainer`, and if they are floating they aren't in one.


### Steps to reproduce

Make any of these docks floating: Import, Filesystem, Node, or History
Open Editor Features (Editor -> Manage Editor Features...)
Make a profile (if you have none) or change a setting on the existing profile

### Minimal reproduction project

n/a
dock_slot[DOCK_SLOT_LEFT_UR]->add_child(ImportDock::get_singleton());
	dock_slot[DOCK_SLOT_LEFT_UR]->set_tab_title(dock_slot[DOCK_SLOT_LEFT_UR]->get_tab_idx_from_control(ImportDock::get_singleton()), TTR("Import"));
	
	dock_slot[DOCK_SLOT_LEFT_BR]->add_child(FileSystemDock::get_singleton());
	dock_slot[DOCK_SLOT_LEFT_BR]->set_tab_title(dock_slot[DOCK_SLOT_LEFT_BR]->get_tab_idx_from_control(FileSystemDock::get_singleton()), TTR("FileSystem"));
	
	dock_slot[DOCK_SLOT_RIGHT_UL]->add_child(InspectorDock::get_singleton());
	dock_slot[DOCK_SLOT_RIGHT_UL]->set_tab_title(dock_slot[DOCK_SLOT_RIGHT_UL]->get_tab_idx_from_control(InspectorDock::get_singleton()), TTR("Inspector"));
	
	dock_slot[DOCK_SLOT_RIGHT_UL]->add_child(NodeDock::get_singleton());
	dock_slot[DOCK_SLOT_RIGHT_UL]->set_tab_title(dock_slot[DOCK_SLOT_RIGHT_UL]->get_tab_idx_from_control(NodeDock::get_singleton()), TTR("Node"));
	
	dock_slot[DOCK_SLOT_RIGHT_UL]->add_child(history_dock);
	dock_slot[DOCK_SLOT_RIGHT_UL]->set_tab_title(dock_slot[DOCK_SLOT_RIGHT_UL]->get_tab_idx_from_control(history_dock), TTR("History"));
	
	dock_slot[DOCK_SLOT_LEFT_UL]->hide();
	dock_slot[DOCK_SLOT_LEFT_BL]->hide();
	dock_slot[DOCK_SLOT_RIGHT_BL]->hide();
	dock_slot[DOCK_SLOT_RIGHT_UR]->hide();
	dock_slot[DOCK_SLOT_RIGHT_BR]->hide();
	left_l_vsplit->hide();
	right_r_vsplit->hide();
	
	left_r_hsplit->set_split_offset(270 * EDSCALE);
	main_hsplit->set_split_offset(-270 * EDSCALE);
	
	const String docks_section = "docks";
	default_layout.instantiate();
	
	default_layout->set_value(docks_section, "dock_3", "Scene,Import");