### 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
main_hsplit->add_child(right_hsplit);
	right_l_vsplit = memnew(VSplitContainer);
	right_hsplit->add_child(right_l_vsplit);
	dock_slot[DOCK_SLOT_RIGHT_UL] = memnew(TabContainer);
	right_l_vsplit->add_child(dock_slot[DOCK_SLOT_RIGHT_UL]);
	dock_slot[DOCK_SLOT_RIGHT_BL] = memnew(TabContainer);
	right_l_vsplit->add_child(dock_slot[DOCK_SLOT_RIGHT_BL]);
	right_r_vsplit = memnew(VSplitContainer);
	right_hsplit->add_child(right_r_vsplit);
	dock_slot[DOCK_SLOT_RIGHT_UR] = memnew(TabContainer);
	right_r_vsplit->add_child(dock_slot[DOCK_SLOT_RIGHT_UR]);
	dock_slot[DOCK_SLOT_RIGHT_BR] = memnew(TabContainer);
	right_r_vsplit->add_child(dock_slot[DOCK_SLOT_RIGHT_BR]);
	
	vsplits.push_back(left_l_vsplit);
	vsplits.push_back(left_r_vsplit);
	vsplits.push_back(right_l_vsplit);
	vsplits.push_back(right_r_vsplit);
	hsplits.push_back(left_l_hsplit);
	hsplits.push_back(left_r_hsplit);
	hsplits.push_back(main_hsplit);
	hsplits.push_back(right_hsplit);
	for (int i = 0; i < vsplits.size(); i++) {
		vsplits[i]->connect("dragged", callable_mp(this, &EditorNode::_dock_split_dragged));
		hsplits[i]->connect("dragged", callable_mp(this, &EditorNode::_dock_split_dragged));
	}
	dock_select_popup = memnew(PopupPanel);
	gui_base->add_child(dock_select_popup);
	VBoxContainer *dock_vb = memnew(VBoxContainer);
	dock_select_popup->add_child(dock_vb);