### 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)

ClassDB::bind_method(D_METHOD("_process_picking"), &Viewport::_process_picking);
#ifndef _3D_DISABLED
	ClassDB::bind_method(D_METHOD("set_world_3d", "world_3d"), &Viewport::set_world_3d);
	ClassDB::bind_method(D_METHOD("get_world_3d"), &Viewport::get_world_3d);
	ClassDB::bind_method(D_METHOD("find_world_3d"), &Viewport::find_world_3d);
	ClassDB::bind_method(D_METHOD("set_use_own_world_3d", "enable"), &Viewport::set_use_own_world_3d);
	ClassDB::bind_method(D_METHOD("is_using_own_world_3d"), &Viewport::is_using_own_world_3d);
	ClassDB::bind_method(D_METHOD("get_camera_3d"), &Viewport::get_camera_3d);
	ClassDB::bind_method(D_METHOD("set_as_audio_listener_3d", "enable"), &Viewport::set_as_audio_listener_3d);
	ClassDB::bind_method(D_METHOD("is_audio_listener_3d"), &Viewport::is_audio_listener_3d);
	ClassDB::bind_method(D_METHOD("set_disable_3d", "disable"), &Viewport::set_disable_3d);
	ClassDB::bind_method(D_METHOD("is_3d_disabled"), &Viewport::is_3d_disabled);
	ClassDB::bind_method(D_METHOD("set_use_xr", "use"), &Viewport::set_use_xr);
	ClassDB::bind_method(D_METHOD("is_using_xr"), &Viewport::is_using_xr);
	ClassDB::bind_method(D_METHOD("set_scaling_3d_mode", "scaling_3d_mode"), &Viewport::set_scaling_3d_mode);
	ClassDB::bind_method(D_METHOD("get_scaling_3d_mode"), &Viewport::get_scaling_3d_mode);
	ClassDB::bind_method(D_METHOD("set_scaling_3d_scale", "scale"), &Viewport::set_scaling_3d_scale);
	ClassDB::bind_method(D_METHOD("get_scaling_3d_scale"), &Viewport::get_scaling_3d_scale);
	ClassDB::bind_method(D_METHOD("set_fsr_sharpness", "fsr_sharpness"), &Viewport::set_fsr_sharpness);
	ClassDB::bind_method(D_METHOD("get_fsr_sharpness"), &Viewport::get_fsr_sharpness);
	ClassDB::bind_method(D_METHOD("set_texture_mipmap_bias", "texture_mipmap_bias"), &Viewport::set_texture_mipmap_bias);
	ClassDB::bind_method(D_METHOD("get_texture_mipmap_bias"), &Viewport::get_texture_mipmap_bias);
	ClassDB::bind_method(D_METHOD("set_vrs_mode", "mode"), &Viewport::set_vrs_mode);
	ClassDB::bind_method(D_METHOD("get_vrs_mode"), &Viewport::get_vrs_mode);
	ClassDB::bind_method(D_METHOD("set_vrs_texture", "texture"), &Viewport::set_vrs_texture);
	ClassDB::bind_method(D_METHOD("get_vrs_texture"), &Viewport::get_vrs_texture);
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "disable_3d"), "set_disable_3d", "is_3d_disabled");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "use_xr"), "set_use_xr", "is_using_xr");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "own_world_3d"), "set_use_own_world_3d", "is_using_own_world_3d");
	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "world_3d", PROPERTY_HINT_RESOURCE_TYPE, "World3D"), "set_world_3d", "get_world_3d");