### 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)

_ensure_node_caches(p_anim);
	ERR_FAIL_COND(p_anim->node_cache.size() != p_anim->animation->get_track_count());
	Animation *a = p_anim->animation.operator->();
#ifdef TOOLS_ENABLED
	bool can_call = is_inside_tree() && !Engine::get_singleton()->is_editor_hint();
#endif 
	bool backward = signbit(p_delta);
	for (int i = 0; i < a->get_track_count(); i++) {
		
		
		if (p_anim->node_cache.size() != a->get_track_count()) {
			_ensure_node_caches(p_anim);
		}
		TrackNodeCache *nc = p_anim->node_cache[i];
		if (!nc) {
			continue; 
		}
		if (!a->track_is_enabled(i)) {
			continue; 
		}
		if (a->track_get_key_count(i) == 0) {
			continue; 
		}
		switch (a->track_get_type(i)) {
			case Animation::TYPE_POSITION_3D: {
#ifndef _3D_DISABLED
				if (!nc->node_3d) {