tensor are included in the reduction
Example:
  >>> src = torch.tensor([1., 2., 3., 4., 5., 6.])
  >>> index = torch.tensor([0, 1, 0, 1, 2, 1])
  >>> input = torch.tensor([1., 2., 3., 4.])
  >>> input.scatter_reduce(0, index, src, reduce="sum")
  tensor([5., 14., 8., 4.])
  >>> input.scatter_reduce(0, index, src, reduce="sum", include_self=False)
  tensor([4., 12., 5., 4.])
  >>> input2 = torch.tensor([5., 4., 3., 2.])
  >>> input2.scatter_reduce(0, index, src, reduce="amax")
  tensor([5., 6., 5., 2.])
  >>> input2.scatter_reduce(0, index, src, reduce="amax", include_self=False)
  tensor([3., 6., 5., 2.])
