### 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)

} else {
					List<int> indices;
					if (p_seeked) {
						int found_key = a->track_find_key(i, p_time);
						if (found_key >= 0) {
							indices.push_back(found_key);
						}
					} else {
						if (p_started) {
							int first_key = a->track_find_key(i, p_prev_time, Animation::FIND_MODE_EXACT);
							if (first_key >= 0) {
								indices.push_back(first_key);
							}
						}
						a->track_get_key_indices_in_range(i, p_time, p_delta, &indices, p_looped_flag);
					}
					for (int &F : indices) {
						Variant value = a->track_get_key_value(i, F);
						value = post_process_key_value(a, i, value, nc->node);
						switch (pa->special) {
							case SP_NONE: {
								bool valid;
								pa->object->set_indexed(pa->subpath, value, &valid); 
#ifdef DEBUG_ENABLED
								if (!valid) {
									ERR_PRINT("Failed setting track value '" + String(pa->owner->path) + "'. Check if the property exists or the type of key is valid. Animation '" + a->get_name() + "' at node '" + get_path() + "'.");
								}
#endif
							} break;
							case SP_NODE2D_POS: {