### 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)

mb->set_position(pos);
#ifdef DEBUG_ENABLED
			if (EngineDebugger::get_singleton() && gui.mouse_focus) {
				Array arr;
				arr.push_back(gui.mouse_focus->get_path());
				arr.push_back(gui.mouse_focus->get_class());
				EngineDebugger::get_singleton()->send_message("scene:click_ctrl", arr);
			}
#endif
			if (mb->get_button_index() == MouseButton::LEFT) { 
				CanvasItem *ci = gui.mouse_focus;
				while (ci) {
					Control *control = Object::cast_to<Control>(ci);
					if (control) {
						if (control->get_focus_mode() != Control::FOCUS_NONE) {
							if (control != gui.key_focus) {
								control->grab_focus();
							}
							break;
						}
						if (control->data.mouse_filter == Control::MOUSE_FILTER_STOP) {
							break;
						}
					}
					if (ci->is_set_as_top_level()) {
						break;
					}
					ci = ci->get_parent_item();
				}
			}