message: Remove redundant test.
  testCollectiveGroupSizeOne already exists in
  tensorflow/python/kernel_tests/collective_ops_test.py.
diff: @@ -274,26 +274,6 @@ class CollectiveOpGPUTest(test.TestCase):
  for result in results:
  self.assertAllClose(result, expected, rtol=1e-5, atol=1e-5)
  - def testCollectiveGroupSizeOne(self):
  - self._setup_context()
  -
  - group_size = 1
  - group_key = 100
  - instance_key = 100
  - in_value = [1., 2., 3., 4.]
  - in_tensor = constant_op.constant(in_value)
  -
  - with ops.device('/GPU:0'):
  - reduced_tensor = collective_ops.all_reduce(
  - in_tensor, group_size, group_key, instance_key, 'Add', 'Id',
  - communication_hint='nccl')
  - self.assertAllEqual(in_value, reduced_tensor.numpy())
  -
  - with ops.device('/GPU:0'):
  - gathered_tensor = collective_ops.all_gather(
  - in_tensor, group_size, group_key, instance_key)
  - self.assertAllEqual(in_value, gathered_tensor.numpy())
  -
  def testNcclStress(self):
  self._setup_context(num_gpus=1)
  