fixed the version of tensorflow-datasets for the testing (#262)

* fixed the version of tensorflow-datasets for the testing

* updated new version of the tensorflow-datasets package because the old one was not compatable with the CI

setup.py

@@ -41,7 +41,7 @@
 
 TESTS_REQUIRE = [
     'pytest',
-    'tensorflow-datasets',
+    'tensorflow-datasets>=4.8.2',
 ]
 
 EXTRAS_REQUIRE = {'test':  TESTS_REQUIRE}