[libc++] [test] Add missing FILE_DEPENDENCIES to align.pass.sh.cpp

libcxx/test/libcxx/atomics/atomics.align/align.pass.sh.cpp

 //===----------------------------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // UNSUPPORTED: libcpp-has-no-threads, c++98, c++03
 // REQUIRES: libatomic
+// FILE_DEPENDENCIES: %t.exe
 // RUN: %{build} -latomic
 // RUN: %{run}
 //
 // GCC currently fails because it needs -fabi-version=6 to fix mangling of
 // std::atomic when used with __attribute__((vector(X))).
 // XFAIL: gcc
 
 // <atomic>