Addressed reviewer's comment.

Change-Id: I143f0a48946689e3e4aed129c770976493c57224

Author: wwwind

tensorflow_model_optimization/g3doc/_index.yaml

@@ -72,6 +72,12 @@ landing_page:
 
   - classname: devsite-landing-row-cards
     items:
+    - heading: "TensorFlow Model Optimization Toolkit — Collaborative Optimization API"
+      path: https://blog.tensorflow.org/2021/10/Collaborative-Optimizations.html
+      buttons:
+      - label: "Read on TensorFlow blog"
+        path: https://blog.tensorflow.org/2021/10/Collaborative-Optimizations.html
+
     - heading: "TensorFlow Model Optimization Toolkit - Weight Clustering API"
       path: https://blog.tensorflow.org/2020/08/tensorflow-model-optimization-toolkit-weight-clustering-api.html
       buttons:
@@ -84,12 +90,6 @@ landing_page:
       - label: "Read on TensorFlow blog"
         path: https://blog.tensorflow.org/2020/04/quantization-aware-training-with-tensorflow-model-optimization-toolkit.html
 
-    - heading: "TensorFlow Model Optimization Toolkit — Collaborative Optimization API"
-      path: https://blog.tensorflow.org/2021/10/Collaborative-Optimizations.html
-      buttons:
-      - label: "Read on TensorFlow blog"
-        path: https://blog.tensorflow.org/2021/10/Collaborative-Optimizations.html
-
     - heading: "TensorFlow Model Optimization Toolkit - Post Training Integer Quantization"
       path: https://blog.tensorflow.org/2019/06/tensorflow-integer-quantization.html
       buttons: