Update TF version requirements

PiperOrigin-RevId: 259451160

Author: broken

oss_scripts/pip_package/setup.py

@@ -73,11 +73,11 @@ def finalize_options(self):
     cmdclass={'install': InstallPlatlib},
     distclass=BinaryDistribution,
     install_requires=[
-        'tensorflow==2.0',
+        'tensorflow>=2.0.0b0, <2.1',
     ],
     extras_require={
         'tensorflow_gpu': [
-            'tensorflow-gpu==2.0',
+            'tensorflow-gpu>=2.0.0b0, <2.1',
         ],
         'tests': [
             'absl-py',