### 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)

VRS_XR,
		VRS_MAX
	};
private:
	friend class ViewportTexture;
	Viewport *parent = nullptr;
	Viewport *gui_parent = nullptr; 
	AudioListener2D *audio_listener_2d = nullptr;
	Camera2D *camera_2d = nullptr;
	HashSet<CanvasLayer *> canvas_layers;
	RID viewport;
	RID current_canvas;
	RID subwindow_canvas;
	bool is_audio_listener_2d_enabled = false;
	RID internal_audio_listener_2d;
	bool override_canvas_transform = false;
	Transform2D canvas_transform_override;
	Transform2D canvas_transform;
	Transform2D global_canvas_transform;
	Transform2D stretch_transform;
	Size2i size = Size2i(512, 512);
	Size2i size_2d_override;
	bool size_allocated = false;
	RID contact_2d_debug;
	RID contact_3d_debug_multimesh;
	RID contact_3d_debug_instance;
	Rect2 last_vp_rect;
	bool transparent_bg = false;
	bool gen_mipmaps = false;
	bool snap_controls_to_pixels = true;