torch support indexing with negative step

The array API standard seems to support negative step.

The basic slice syntax is i:j:k where i is the starting index, j is the stopping index, and k is the step (k != 0).

But array-api-compat.torch tensors do not:

from array_api_compat import torch
x = torch.arange(10)
x[::-1]  # ValueError: step must be greater than zero

Adding support for negative step would be appreciated! (In the meantime, I can use flip.) Thanks for considering it.

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