[TFMG] Update pip package version for 2.20.0 release

PiperOrigin-RevId: 868232215

Author: tensorflower-gardener

official/pip_package/setup.py

@@ -20,8 +20,8 @@
 from setuptools import find_packages
 from setuptools import setup
 
-version = '2.19.0'
-tf_version = '2.19.0'  # Major version.
+version = '2.20.0'
+tf_version = '2.20.0'  # Major version.
 
 project_name = 'tf-models-official'