### Godot version

4.0beta17

### System information

Linux Mint 21.1

### Issue description

When editing animations for the **frame** property of **Sprite2D**, the preview image does not respect the **region_rect** specified in the Sprite2D's properties.

Godot 4.0 (tested with alpha1 to beta17)
![Screenshot from 2023-02-05 21-19-29](https://user-images.githubusercontent.com/2348534/216868394-45a9dc42-ce4b-4b11-82cb-4491aea46d9b.png)

Godot 3.5
![Screenshot from 2023-02-05 21-19-43](https://user-images.githubusercontent.com/2348534/216868543-cff6eb60-a431-4138-8fa6-5c30a54de0e1.png)

As can be seen in the second screenshot, the region rect is applied to the key preview image in Godot 3.5, but is ignored in Godot 4.0.


### Steps to reproduce

Steps:

1. Set a region rect on a Sprite2D node
2. Add Sprite2D.frame as a track to an AnimationPlayer
3. Insert key
4. Key preview does not take region rect into account

### Minimal reproduction project

[MRP.zip](https://github.com/godotengine/godot/files/10637055/MRP.zip)

}
	AnimationTrackEdit::drop_data(p_point, p_data);
}
void AnimationTrackEditTypeAudio::gui_input(const Ref<InputEvent> &p_event) {
	ERR_FAIL_COND(p_event.is_null());
	Ref<InputEventMouseMotion> mm = p_event;
	if (!len_resizing && mm.is_valid()) {
		bool use_hsize_cursor = false;
		for (int i = 0; i < get_animation()->track_get_key_count(get_track()); i++) {
			Ref<AudioStream> stream = get_animation()->audio_track_get_key_stream(get_track(), i);
			if (!stream.is_valid()) {
				continue;
			}
			float start_ofs = get_animation()->audio_track_get_key_start_offset(get_track(), i);
			float end_ofs = get_animation()->audio_track_get_key_end_offset(get_track(), i);
			float len = stream->get_length();
			if (len == 0) {
				Ref<AudioStreamPreview> preview = AudioStreamPreviewGenerator::get_singleton()->generate_preview(stream);
				float preview_len = preview->get_length();
				len = preview_len;
			}
			len -= end_ofs;
			len -= start_ofs;
			if (get_animation()->track_get_key_count(get_track()) > i + 1) {
				len = MIN(len, get_animation()->track_get_key_time(get_track(), i + 1) - get_animation()->track_get_key_time(get_track(), i));
			}
			float ofs = get_animation()->track_get_key_time(get_track(), i);
			ofs -= get_timeline()->get_value();
			ofs *= get_timeline()->get_zoom_scale();
			ofs += get_timeline()->get_name_limit();