Tests: Fix warning clang-analyzer-cplusplus.NewDeleteLeaks

Fix the warning: `potential leak of memory pointed to by "vp"`.

Tests/CompileFeatures/cxx_contextual_conversions.cpp

-
 #define assert(E)                                                             \
   if (!(E))                                                                   \
     return 1;
@@ -38,6 +37,7 @@ int someFunc()
   }
 
   int* vp = new int[i];
+  delete[] vp;
 
   return 0;
 }