### 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)

#include "animation_player.h"
#include "core/config/engine.h"
#include "core/object/message_queue.h"
#include "scene/scene_string_names.h"
#include "servers/audio/audio_stream.h"
#ifdef TOOLS_ENABLED
#include "editor/editor_node.h"
#include "editor/editor_undo_redo_manager.h"
#include "scene/2d/skeleton_2d.h"
void AnimatedValuesBackup::update_skeletons() {