### Godot version

4.0.beta13

### System information

Windows 10

### Issue description

When you call the `seek()` function without a current animation it outputs `Condition "!playback.current.from" is true.` to the debugger.

I was getting the error above whenever I would call `stop()` on an AnimationPlayer when it didn't have a playing animation. I realized that `stop()` also calls the `seek()` function.

I would expect the `seek()` and `stop()` functions to just do nothing, instead of throwing errors, if there isn't a current animation, or at least show an error that says that there is no animation to seek/stop.

This is the same issue that was described here: [#6122](https://github.com/godotengine/godot/issues/6122)

### Steps to reproduce

- Create an AnimationPlayer node.
- Don't have it play any animations.
- Call the `seek()` function.

### Minimal reproduction project

[seek_issue.zip](https://github.com/godotengine/godot/files/10442071/seek_issue.zip)

return; 
		}
		_animation_update_transforms();
		if (end_reached) {
			if (queued.size()) {
				String old = playback.assigned;
				play(queued.front()->get());
				String new_name = playback.assigned;
				queued.pop_front();
				if (end_notify) {
					emit_signal(SceneStringNames::get_singleton()->animation_changed, old, new_name);
				}
			} else {
				playing = false;
				_set_process(false);
				if (end_notify) {
					emit_signal(SceneStringNames::get_singleton()->animation_finished, playback.assigned);
					if (movie_quit_on_finish && OS::get_singleton()->has_feature("movie")) {
						print_line(vformat("Movie Maker mode is enabled. Quitting on animation finish as requested by: %s", get_path()));
						get_tree()->quit();
					}
				}
			}
			end_reached = false;
		}
	} else {
		_set_process(false);
	}
}
void AnimationPlayer::_animation_set_cache_update() {