Reorder imports in torch_test_contrib_gpu (facebookresearch#3761)

Summary:
Pull Request resolved: facebookresearch#3761

This fixes CUDA errors inside faiss in the test environment. If torch is loaded first (this change) then both torch and faiss see all GPUs available on the machine in the ROCm build. Without this change, torch sees the GPUs and faiss does not. AMD team is looking at finding the root cause but we wanted to fix this for now.

Reviewed By: junjieqi, mnorris11

Differential Revision: D61358018

fbshipit-source-id: ac59be99817ef13d37a1676f615585f44eabaf24

faiss/gpu/test/torch_test_contrib_gpu.py

@@ -3,10 +3,10 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
-import faiss
 import torch
 import unittest
 import numpy as np
+import faiss
 import faiss.contrib.torch_utils
 
 def to_column_major_torch(x):