### Godot version

4.0.rc

### System information

Any

### Issue description

If the RESET animation is generated at the same time as the Bezier track is generated, the bezier edit button will not be active.

![image](https://user-images.githubusercontent.com/61938263/218256176-88b1b196-7b6b-4404-84ad-e8694f23bb1b.png)

Also, if you delete a track in the Bezier Editor, or in undo redo, it will not update correctly.

### Steps to reproduce

![image](https://user-images.githubusercontent.com/61938263/218256230-4b0219d5-87e4-453a-8294-59f8feb0cfd5.png)


### Minimal reproduction project

N/A
return animation;
}
void AnimationTrackEditor::_root_removed() {
	root = nullptr;
}
void AnimationTrackEditor::set_root(Node *p_root) {
	if (root) {
		root->disconnect("tree_exiting", callable_mp(this, &AnimationTrackEditor::_root_removed));
	}
	root = p_root;
	if (root) {
		root->connect("tree_exiting", callable_mp(this, &AnimationTrackEditor::_root_removed), CONNECT_ONE_SHOT);
	}
	_update_tracks();
}
Node *AnimationTrackEditor::get_root() const {