Regression tests failing due to numerical differences

[not-jenni]

lightning_i8_test.py, magenta_test.py, visual_wake_words_i8_test.py began failing on August 20th:

https://github.com/iree-org/iree-samples/runs/7944684175?check_suite_focus=true

Max error (0): 0.372814
[  FAILED  ] LightningI8Test.test_compile_tflite

Max error (0): 0.238547
[  FAILED  ] MagentaTest.test_compile_tflite

Max error (0): 2.000000
[  FAILED  ] VisualWakeWordsTest.test_compile_tflite

[not-jenni]

This failure is due to updating to tf-nightly==2.11.0.dev20220820, at this commit: tensorflow/tensorflow@e6da934