Fix thumbnail path for KerasHub integration post

Corrected the thumbnail image path in the blog configuration for the 'Announcing New Hugging Face and KerasHub integration' post.

Author: julien-c

_blog.yml

@@ -4334,7 +4334,7 @@
 
 - local: keras-hub-integration
   title: "Announcing New Hugging Face and KerasHub integration"
-  thumbnail: /blog/assets/keras-nlp-integration/thumbnail.png
+  thumbnail: /blog/assets/keras-hub-integration/thumbnail.png
   author: ariG23498
   date: Jul 10, 2024
   tags: