Alembic export: assume that transforms are always animated

This is a partial rollback of f18ad385df. It
turned out to be more tricky to determine animatedness of an object.

This fixes T71986.

source/blender/alembic/intern/abc_transform.cc

@@ -134,7 +134,7 @@ Imath::Box3d AbcTransformWriter::bounds()
 
 bool AbcTransformWriter::hasAnimation(Object *ob) const
 {
-  return !BLI_listbase_is_empty(&ob->constraints) || BKE_animdata_id_is_animated(&ob->id);
+  return true;
 }
 
 /* ************************************************************************** */