fix possible pandas import error during tensorboard tests (#29650)

Summary:
TensorBoard tests using SummaryWriter() may fail with a pandas import
complaint if TensorFlow packages are installed in the same python
environment as PyTorch:

Traceback (most recent call last):
  File "test_tensorboard.py", line 212, in test_writer
    with self.createSummaryWriter() as writer:
  File "test_tensorboard.py", line 64, in createSummaryWriter
    return SummaryWriter(temp_dir)
...
  File "[...]/site-packages/pandas/core/arrays/categorical.py", line 52, in <module>
    import pandas.core.algorithms as algorithms
AttributeError: module 'pandas' has no attribute 'core'

The exact failure may depend on the pandas version. We've also seen:

  File "[...]/site-packages/pandas/core/arrays/categorical.py", line 9, in <module>
    import pandas.compat as compat
AttributeError: module 'pandas' has no attribute 'compat'

The module import chain leading to the failure is tensorboard imports
tensorflow imports tensorflow_estimator imports pandas. pandas includes
a submodule named 'bottleneck', whose name collides with the PyTorch
'test/bottleneck/' subdirectory.

So IF tensorboard, tensorflow, tensorflow_estimator, and pandas are
installed in the python environment AND IF testing is run from within
PyTorch's 'test/' directory (or maybe just with 'test/' in PYTHONPATH,
etc.), then TensorBoard tests using SummaryWriter() will fail.

Rename the 'bottleneck/' directory slightly to avoid the name collision.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/29650

Differential Revision: D19698638

Pulled By: ezyang

fbshipit-source-id: cb59342ed407cb37aefc833d67f768a8809129ac

test/test_utils.py

@@ -356,11 +356,11 @@ class TestBottleneck(TestCase):
 
     def _check_run_args(self):
         # Check that this fails due to missing args
-        rc, out, err = self._run_bottleneck('bottleneck/test_args.py')
+        rc, out, err = self._run_bottleneck('bottleneck_test/test_args.py')
         self.assertEqual(rc, 2, None, self._fail_msg('Missing args should error', out + err))
 
         # This should succeed
-        rc, out, err = self._run_bottleneck('bottleneck/test_args.py', '--foo foo --bar bar')
+        rc, out, err = self._run_bottleneck('bottleneck_test/test_args.py', '--foo foo --bar bar')
         self.assertEqual(rc, 0, None, self._fail_msg('Should pass args to script', out + err))
 
     def _fail_msg(self, msg, output):
@@ -404,7 +404,7 @@ class TestBottleneck(TestCase):
 
     @unittest.skipIf(HAS_CUDA, 'CPU-only test')
     def test_bottleneck_cpu_only(self):
-        rc, out, err = self._run_bottleneck('bottleneck/test.py')
+        rc, out, err = self._run_bottleneck('bottleneck_test/test.py')
         self.assertEqual(rc, 0, 'Run failed with\n{}'.format(err))
 
         self._check_run_args()
@@ -416,7 +416,7 @@ class TestBottleneck(TestCase):
     @unittest.skipIf(not HAS_CUDA, 'No CUDA')
     @skipIfRocm
     def test_bottleneck_cuda(self):
-        rc, out, err = self._run_bottleneck('bottleneck/test_cuda.py')
+        rc, out, err = self._run_bottleneck('bottleneck_test/test_cuda.py')
         self.assertEqual(rc, 0, 'Run failed with\n{}'.format(err))
 
         self._check_run_args()