### 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)

}
AnimationTrackEditTypeAudio::AnimationTrackEditTypeAudio() {
	AudioStreamPreviewGenerator::get_singleton()->connect("preview_updated", callable_mp(this, &AnimationTrackEditTypeAudio::_preview_changed));
}
bool AnimationTrackEditTypeAudio::can_drop_data(const Point2 &p_point, const Variant &p_data) const {
	if (p_point.x > get_timeline()->get_name_limit() && p_point.x < get_size().width - get_timeline()->get_buttons_width()) {
		Dictionary drag_data = p_data;
		if (drag_data.has("type") && String(drag_data["type"]) == "resource") {
			Ref<AudioStream> res = drag_data["resource"];
			if (res.is_valid()) {
				return true;
			}
		}
		if (drag_data.has("type") && String(drag_data["type"]) == "files") {
			Vector<String> files = drag_data["files"];
			if (files.size() == 1) {
				String file = files[0];
				Ref<AudioStream> res = ResourceLoader::load(file);
				if (res.is_valid()) {
					return true;
				}
			}
		}
	}
	return AnimationTrackEdit::can_drop_data(p_point, p_data);
}
void AnimationTrackEditTypeAudio::drop_data(const Point2 &p_point, const Variant &p_data) {