### 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)

#include "scene/gui/popup_menu.h"
#include "scene/gui/subviewport_container.h"
#include "scene/main/canvas_layer.h"
#include "scene/main/window.h"
#include "scene/resources/mesh.h"
#include "scene/resources/text_line.h"
#include "scene/resources/world_2d.h"
#include "scene/scene_string_names.h"
#include "servers/audio_server.h"
#include "servers/rendering/rendering_server_globals.h"
void ViewportTexture::setup_local_to_scene() {
	if (vp_pending) {
		return;
	}
	Node *loc_scene = get_local_scene();
	if (!loc_scene) {
		return;
	}
	if (vp) {
		vp->viewport_textures.erase(this);
		vp = nullptr;
	}
	if (loc_scene->is_ready()) {
		_setup_local_to_scene(loc_scene);
	} else {
		loc_scene->connect(SNAME("ready"), callable_mp(this, &ViewportTexture::_setup_local_to_scene).bind(loc_scene), CONNECT_ONE_SHOT);
		vp_pending = true;
	}
}
void ViewportTexture::set_viewport_path_in_scene(const NodePath &p_path) {