### 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
AnimationPlayer *player = AnimationPlayerEditor::get_singleton()->get_player();
	edit->get_popup()->set_item_disabled(edit->get_popup()->get_item_index(EDIT_APPLY_RESET), !player->can_apply_reset());
}
void AnimationTrackEditor::goto_prev_step(bool p_from_mouse_event) {
	if (animation.is_null()) {
		return;
	}
	float anim_step = animation->get_step();
	if (anim_step == 0) {
		anim_step = 1;
	}
	if (p_from_mouse_event && Input::get_singleton()->is_key_pressed(Key::SHIFT)) {
		
		
		anim_step *= 0.25;
	}
	float pos = timeline->get_play_position();
	pos = Math::snapped(pos - anim_step, anim_step);
	if (pos < 0) {
		pos = 0;
	}
	set_anim_pos(pos);
	emit_signal(SNAME("timeline_changed"), pos, true, false);
}
void AnimationTrackEditor::goto_next_step(bool p_from_mouse_event, bool p_timeline_only) {