Change Error unittest to use the LLVM_ENABLE_ABI_BREAKING_CHECKS instead of NDEBUG

This is consistent with the header (after r288087) and fixes the
test for the configuration:
  -DLLVM_ENABLE_ASSERTIONS=ON -DLLVM_ABI_BREAKING_CHECKS=FORCE_OFF




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288196 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed