Bump up atol for test_bilinear_resize_op to fix flakiness

[haojin2]

Description

As title.

Checklist

Essentials

Please feel free to remove inapplicable items for your PR.

• The PR title starts with [MXNET-$JIRA_ID], where $JIRA_ID refers to the relevant JIRA issue created (except PRs with tiny changes)
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• Unit tests are added for small changes to verify correctness (e.g. adding a new operator)
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• To the my best knowledge, examples are either not affected by this change, or have been fixed to be compatible with this change

Changes

• As title

Comments

This test is a bit too long (~317 seconds for 10 trials) so not able to verify 10000 times. Proving the fix with a before-after comparison.
Before:

MXNET_TEST_SEED=1608036320 nosetests tests/python/gpu/test_operator_gpu.py:test_bilinear_resize_op
[INFO] Setting module np/mx/python random seeds, use MXNET_MODULE_SEED=354422934 to reproduce.
[WARNING] *** test-level seed set: all "@with_seed()" tests run deterministically ***
[INFO] Setting test np/mx/python random seeds, use MXNET_TEST_SEED=1608036320 to reproduce.
F
======================================================================
FAIL: test_operator_gpu.test_bilinear_resize_op
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/nose/case.py", line 197, in runTest
    self.test(*self.arg)
  File "/usr/lib/python3/dist-packages/nose/util.py", line 620, in newfunc
    return func(*arg, **kw)
  File "/home/ubuntu/9-mxnet/tests/python/gpu/../unittest/common.py", line 177, in test_new
    orig_test(*args, **kwargs)
  File "/home/ubuntu/9-mxnet/tests/python/gpu/../unittest/test_operator.py", line 7407, in test_bilinear_resize_op
    check_bilinear_resize_modes_op(shape_0, shape_1=shape_1, mode='like')
  File "/home/ubuntu/9-mxnet/tests/python/gpu/../unittest/test_operator.py", line 7381, in check_bilinear_resize_modes_op
    check_numeric_gradient(resize_sym, [data_np, date_np_like])
  File "/home/ubuntu/9-mxnet/python/mxnet/test_utils.py", line 980, in check_numeric_gradient
    ("NUMERICAL_%s"%name, "BACKWARD_%s"%name))
  File "/home/ubuntu/9-mxnet/python/mxnet/test_utils.py", line 503, in assert_almost_equal
    raise AssertionError(msg)
AssertionError: 
Items are not equal:
Error 1.004549 exceeds tolerance rtol=0.010000, atol=0.000000.  Location of maximum error:(1, 0, 12, 12), a=0.004321, b=0.004278
 NUMERICAL_data: array([[[[0.84230304, 0.        , 0.57831407, ..., 0.1641959 ,
          0.        , 0.331074  ],
         [0.        , 0.        , 0.        , ..., 0.        ,...
 BACKWARD_data: array([[[[0.84230524, 0.        , 0.5783209 , ..., 0.16419744,
          0.        , 0.33107594],
         [0.        , 0.        , 0.        , ..., 0.        ,...
-------------------- >> begin captured logging << --------------------
common: INFO: Setting module np/mx/python random seeds, use MXNET_MODULE_SEED=354422934 to reproduce.
common: WARNING: *** test-level seed set: all "@with_seed()" tests run deterministically ***
common: INFO: Setting test np/mx/python random seeds, use MXNET_TEST_SEED=1608036320 to reproduce.
--------------------- >> end captured logging << ---------------------

----------------------------------------------------------------------
Ran 1 test in 45.946s

FAILED (failures=1)

After:

MXNET_TEST_SEED=1608036320 nosetests tests/python/gpu/test_operator_gpu.py:test_bilinear_resize_op
[INFO] Setting module np/mx/python random seeds, use MXNET_MODULE_SEED=1573659249 to reproduce.
[WARNING] *** test-level seed set: all "@with_seed()" tests run deterministically ***
[INFO] Setting test np/mx/python random seeds, use MXNET_TEST_SEED=1608036320 to reproduce.
.
----------------------------------------------------------------------
Ran 1 test in 47.239s

OK

[haojin2]

Fix for #14902.

[haojin2]

@marcoabreu Ping for review

[haojin2]

@perdasilva Please give an approval if you think this is good to go, thanks!