[tests] enable XPU backend for `test_zero3_integration`

[faaany]

What does this PR do?

python -m pytest -rA -k "test_zero3_integration" tests/deepspeed

The command above gives the following error:

E           Traceback (most recent call last):
E             File "/home/fanli/workspace/accelerate/src/accelerate/test_utils/scripts/external_deps/test_zero3_integration.py", line 52, in <module>
E               main()
E             File "/home/fanli/workspace/accelerate/src/accelerate/test_utils/scripts/external_deps/test_zero3_integration.py", line 48, in main
E               init_torch_dist_then_launch_deepspeed()
E             File "/home/fanli/workspace/accelerate/src/accelerate/test_utils/scripts/external_deps/test_zero3_integration.py", line 30, in init_torch_dist_then_launch_deepspeed
E               torch.distributed.init_process_group(backend="nccl")
E             File "/home/fanli/miniforge3/envs/acc-ut-ww23/lib/python3.9/site-packages/torch/distributed/c10d_logger.py", line 75, in wrapper
E               return func(*args, **kwargs)
E             File "/home/fanli/miniforge3/envs/acc-ut-ww23/lib/python3.9/site-packages/torch/distributed/c10d_logger.py", line 89, in wrapper
E               func_return = func(*args, **kwargs)
E             File "/home/fanli/miniforge3/envs/acc-ut-ww23/lib/python3.9/site-packages/torch/distributed/distributed_c10d.py", line 1312, in init_process_group
E               default_pg, _ = _new_process_group_helper(
E             File "/home/fanli/miniforge3/envs/acc-ut-ww23/lib/python3.9/site-packages/torch/distributed/distributed_c10d.py", line 1513, in _new_process_group_helper
E               raise RuntimeError("Distributed package doesn't have NCCL built in")
E           RuntimeError: Distributed package doesn't have NCCL built in
E           /home/fanli/miniforge3/envs/acc-ut-ww23/lib/python3.9/site-packages/torch/distributed/distributed_c10d.py:613: UserWarning: Attempted to get default timeout for nccl backend, but NCCL support is not compiled
E             warnings.warn("Attempted to get default timeout for nccl backend, but NCCL support is not compiled")

Pls let me know if I need to add support for other devices as well. @muellerzr @SunMarc

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[faaany]

@SunMarc can we proceed with merging? Thanks so much!