### 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)

{
		Transform3D t;
		for (int i = 0; i < cache_update_size; i++) {
			TrackNodeCache *nc = cache_update[i];
			ERR_CONTINUE(nc->accum_pass != accum_pass);
#ifndef _3D_DISABLED
			if (nc->skeleton && nc->bone_idx >= 0) {
				if (nc->loc_used) {
					nc->skeleton->set_bone_pose_position(nc->bone_idx, nc->loc_accum);
				}
				if (nc->rot_used) {
					nc->skeleton->set_bone_pose_rotation(nc->bone_idx, nc->rot_accum);
				}
				if (nc->scale_used) {
					nc->skeleton->set_bone_pose_scale(nc->bone_idx, nc->scale_accum);
				}
			} else if (nc->node_blend_shape) {
				nc->node_blend_shape->set_blend_shape_value(nc->blend_shape_idx, nc->blend_shape_accum);
			} else if (nc->node_3d) {
				if (nc->loc_used) {
					nc->node_3d->set_position(nc->loc_accum);
				}
				if (nc->rot_used) {
					nc->node_3d->set_rotation(nc->rot_accum.get_euler());
				}
				if (nc->scale_used) {
					nc->node_3d->set_scale(nc->scale_accum);
				}
			}
#endif