chore: updated README with links to Vertex AI migration guide (#369)

Co-authored-by: Dan Lee <[email protected]>

Co-authored-by: Dan Lee <[email protected]>

Author: rosiezou

packages/google-cloud-automl/README.rst

@@ -1,8 +1,13 @@
 Python Client for Cloud AutoML API
 ==================================
-
 |ga| |pypi| |versions| 
 
+AutoML API Python Client is now available in the new Vertex AI.
+Migrate your AutoML resources to Vertex AI to get the latest features
+like data labeling, AutoML-powered training, and endpoint management. 
+
+- `Migrate to Vertex AI Documentation`_
+
 The `Cloud AutoML API`_ is a suite of machine learning products that enables
 developers with limited machine learning expertise to train high-quality models
 specific to their business needs, by leveraging Google’s state-of-the-art
@@ -20,6 +25,7 @@ transfer learning, and Neural Architecture Search technology.
 .. _Cloud AutoML API: https://cloud.google.com/automl
 .. _Client Library Documentation: https://cloud.google.com/python/docs/reference/automl/latest
 .. _Product Documentation:  https://cloud.google.com/automl
+.. _Migrate to Vertex AI Documentation: https://cloud.google.com/vertex-ai/docs/start/migrating-to-vertex-ai
 
 Quick Start
 -----------