Bump TF to 2.6.0 and ready for 0.20.0 release (#1495)
Bump TF to 2.6.0 and ready for 0.20.0 release (#1495)

This PR bump TF to 2.6.0 and ready for 0.20.0 release.

Signed-off-by: Yong Tang <765086fe2e0c1f980161f127fec596800f327f62@outlook.com>
tensorflow/io,tensorflow/io,tensorflow/io,tensorflow/io,tensorflow/io,tensorflow/io,tensorflow/io