### Godot version

4.1.dev 2e273f0e35800f2bcc7c05db54100caa97928f69

### System information

macOS 13.4

### Issue description

Removing a SpinBox from the node tree using `remove_child` during the line edit text submit signal will crash the engine.

```
handle_crash: Program crashed with signal 11
Engine version: Godot Engine v4.1.dev.custom_build (2e273f0e35800f2bcc7c05db54100caa97928f69)
Dumping the backtrace. Please include this when reporting the bug to the project developer.
[1] 1   libsystem_platform.dylib            0x0000000183b5aa24 _sigtramp + 56
[2] Viewport::gui_get_focus_owner() (in godot.macos.editor.arm64) + 32
[3] SpinBox::_line_edit_focus_exit() (in godot.macos.editor.arm64) + 28
[4] CallQueue::_call_function(Callable const&, Variant const*, int, bool) (in godot.macos.editor.arm64) + 336
[5] CallQueue::flush() (in godot.macos.editor.arm64) + 908
[6] SceneTree::physics_process(double) (in godot.macos.editor.arm64) + 244
[7] Main::iteration() (in godot.macos.editor.arm64) + 528
```

### Steps to reproduce

Open the minimal reproduction project, click on the SpinBox, press enter, and the engine crashes.

### Minimal reproduction project

[SpinBoxTextSubmitCrash.zip](https://github.com/godotengine/godot/files/11631081/SpinBoxTextSubmitCrash.zip)

HashMap<int, ObjectID> touch_focus;
		Control *mouse_focus = nullptr;
		Control *last_mouse_focus = nullptr;
		Control *mouse_click_grabber = nullptr;
		BitField<MouseButtonMask> mouse_focus_mask;
		Control *key_focus = nullptr;
		Control *mouse_over = nullptr;
		Control *drag_mouse_over = nullptr;
		Vector2 drag_mouse_over_pos;
		Control *tooltip_control = nullptr;
		Window *tooltip_popup = nullptr;
		Label *tooltip_label = nullptr;
		Point2 tooltip_pos;
		Point2 last_mouse_pos;
		Point2 drag_accum;
		bool drag_attempted = false;
		Variant drag_data;
		ObjectID drag_preview_id;
		Ref<SceneTreeTimer> tooltip_timer;
		double tooltip_delay = 0.0;
		bool roots_order_dirty = false;
		List<Control *> roots;
		HashSet<ObjectID> canvas_parents_with_dirty_order;
		int canvas_sort_index = 0; 
		bool dragging = false;
		bool drag_successful = false;
		bool embed_subwindows_hint = false;
		Window *subwindow_focused = nullptr;
		SubWindowDrag subwindow_drag = SUB_WINDOW_DRAG_DISABLED;
		Vector2 subwindow_drag_from;