[PHI]Fix paddle.stack to support big Tensor

Author: DanielSun11

paddle/phi/infermeta/backward.cc

@@ -1750,7 +1750,7 @@ void StackGradInferMeta(const MetaTensor& out_grad,
           x_grad.size(),
           static_cast<size_t>(dy_dim[axis])));
 
-  auto vec = common::vectorize<int>(dy_dim);
+  auto vec = common::vectorize<int64_t>(dy_dim);
   vec.erase(vec.begin() + axis);
 
   for (auto& grad : x_grad) {