Fixed the code in transfer_learning_with_hub.ipynb

[tilakrayal]

https://www.tensorflow.org/tutorials/images/transfer_learning_with_hub document is failing in the Tensorflow v2.18 which contains Keras3.0. Modified the code to the Keras2.0.

Kindly find the gist for the reference.

Fixes #tensorflow/tensorflow#83279

[github-actions]

Preview

Preview and run these notebook edits with Google Colab:

• site/en/tutorials/images/transfer_learning_with_hub.ipynb

Rendered notebook diffs available on ReviewNB.com.

Format and style

Use the TensorFlow docs notebook tools to format for consistent source diffs and lint for style:

$ python3 -m pip install -U --user git+https://github.com/tensorflow/docs

$ python3 -m tensorflow_docs.tools.nbfmt notebook.ipynb

$ python3 -m tensorflow_docs.tools.nblint --arg=repo:tensorflow/docs notebook.ipynb

If commits are added to the pull request, synchronize your local branch: git pull origin patch-18