Move the TFLite test_util.py local to the test directory. (#8265)

* This should never have been exported as part of the distribution.

integrations/tensorflow/test/python/iree_tfl_tests/mobilenet_v1_test.py

diff --git a/integrations/tensorflow/test/python/iree_tfl_tests/mobilenet_v1_test.py b/integrations/tensorflow/test/python/iree_tfl_tests/mobilenet_v1_test.py
index 7286eff..ab9f15d 100644
--- a/integrations/tensorflow/test/python/iree_tfl_tests/mobilenet_v1_test.py
+++ b/integrations/tensorflow/test/python/iree_tfl_tests/mobilenet_v1_test.py
@@ -6,7 +6,7 @@
 
 import absl.testing
 import numpy
-import iree.tflite.support.test_util as test_util
+from . import test_util
 
 model_path = "https://storage.googleapis.com/iree-model-artifacts/tflite-integration-tests/mobilenet_v1.tflite"
 

integrations/tensorflow/test/python/iree_tfl_tests/posenet_i8_test.py

diff --git a/integrations/tensorflow/test/python/iree_tfl_tests/posenet_i8_test.py b/integrations/tensorflow/test/python/iree_tfl_tests/posenet_i8_test.py
index b40ae5e..3ec3540 100644
--- a/integrations/tensorflow/test/python/iree_tfl_tests/posenet_i8_test.py
+++ b/integrations/tensorflow/test/python/iree_tfl_tests/posenet_i8_test.py
@@ -5,7 +5,7 @@
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
 import absl.testing
-import iree.tflite.support.test_util as test_util
+from . import test_util
 import numpy
 import urllib.request
 

integrations/tensorflow/test/python/iree_tfl_tests/test_util.py

diff --git a/integrations/tensorflow/python_projects/iree_tflite/iree/tflite/support/test_util.py b/integrations/tensorflow/test/python/iree_tfl_tests/test_util.py
similarity index 100%
rename from integrations/tensorflow/python_projects/iree_tflite/iree/tflite/support/test_util.py
rename to integrations/tensorflow/test/python/iree_tfl_tests/test_util.py