Fix tfds install and add tf-addons to r2.2.0 requirements

Author: allenwang28

official/requirements.txt

@@ -9,9 +9,10 @@ pandas>=0.22.0
 psutil>=5.4.3
 py-cpuinfo>=3.3.0
 scipy>=0.19.1
+tensorflow-datasets
+tensorflow-addons
 tensorflow-hub>=0.6.0
 tensorflow-model-optimization>=0.2.1
-tensorflow_datasets
 dataclasses
 gin-config
 typing