Fix import mistake.

Author: mingxingtan

efficientdet/dataloader_test.py

@@ -18,7 +18,7 @@
 
 import dataloader
 import hparams_config
-from brain_automl.efficientdet import test_util
+import test_util
 
 from keras import anchors
 from object_detection import tf_example_decoder

efficientdet/keras/inference_test.py

@@ -17,7 +17,7 @@
 import tempfile
 from absl import logging
 import tensorflow as tf
-from brain_automl.efficientdet import test_util
+import test_util
 from keras import efficientdet_keras
 from keras import inference