Try to fix external_symbolizer_path.cpp test to stop breaking on buildbots.

Not sure what the issue is, but it might be because the test copies
llvm-symbolizer to a different directory, and it can't find libc++.
Try to add some REQUIRES that we use in other tests where we copy
llvm tools out of their original directories.

GitOrigin-RevId: 394913fdb96af1a8ab699140f23073f2f366f406
1 file changed