[test] Silence another unused-typedef warning

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@300581 91177308-0d34-0410-b5e6-96231b3b80d8

test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move_convert.runtime.pass.cpp

@@ -78,7 +78,6 @@ void test_sfinae() {
   using DA = NCConvertingDeleter<A[]>;        // non-copyable deleters
   using DAC = NCConvertingDeleter<const A[]>; // non-copyable deleters
 
-  using DB = NCConvertingDeleter<B[]>;
   using UA = std::unique_ptr<A[]>;
   using UAC = std::unique_ptr<const A[]>;
   using UAD = std::unique_ptr<A[], DA>;