### Godot version

4.2 1ba920f

### System information

Windows 10.0.19045 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1060 (NVIDIA; 30.0.15.1403) - Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz (8 Threads)

### Issue description

```GDScript
func _ready() -> void:
	$AnimationPlayer.play("new_animation")
	$AnimationPlayer.advance(0)
```
The animation has a single track with Update Mode set to discrete. It does not play, no matter the argument used.
Removing `advance()` will make it play.

Works correctly in rc1.

### Steps to reproduce

1. Run MRP on master
2. Run MRP in 4.2 rc1

### Minimal reproduction project

[brokedvance.zip](https://github.com/godotengine/godot/files/13460977/brokedvance.zip)

playback.started = false; 
	AnimationMixer::advance(p_time);
}
bool AnimationPlayer::is_valid() const {
	return (playback.current.from);
}
double AnimationPlayer::get_current_animation_position() const {
	ERR_FAIL_NULL_V_MSG(playback.current.from, 0, "AnimationPlayer has no current animation.");
	return playback.current.pos;
}
double AnimationPlayer::get_current_animation_length() const {
	ERR_FAIL_NULL_V_MSG(playback.current.from, 0, "AnimationPlayer has no current animation.");
	return playback.current.from->animation->get_length();
}
void AnimationPlayer::set_autoplay(const String &p_name) {
	if (is_inside_tree() && !Engine::get_singleton()->is_editor_hint()) {
		WARN_PRINT("Setting autoplay after the node has been added to the scene has no effect.");
	}
	autoplay = p_name;
}
String AnimationPlayer::get_autoplay() const {