Fix #121766: Softbody ensure current position

When reading a cached frame the unmodified goal positions are not
synchronized along. Now fixed.

Co-authored by @bjornmose

Pull Request: https://projects.blender.org/blender/blender/pulls/121768

source/blender/blenkernel/intern/softbody.cc

@@ -3600,6 +3600,8 @@ void sbObjectStep(Depsgraph *depsgraph,
   if (cache_result == PTCACHE_READ_EXACT || cache_result == PTCACHE_READ_INTERPOLATED ||
       (!can_simulate && cache_result == PTCACHE_READ_OLD))
   {
+    /* Keep goal positions in track. */
+    softbody_update_positions(ob, sb, vertexCos, numVerts);
     softbody_to_object(ob, vertexCos, numVerts, sb->local);
 
     BKE_ptcache_validate(cache, framenr);