Removed horovod samples (#3434)

These samples were not compatible with tensorflow 2.16, which is required to avoid security vulnerabilities

cli/README.md

@@ -97,7 +97,6 @@ path|status|description
 [jobs/single-step/scikit-learn/iris/job-docker-context.yml](jobs/single-step/scikit-learn/iris/job-docker-context.yml)|[![jobs/single-step/scikit-learn/iris/job-docker-context](https://github.com/Azure/azureml-examples/workflows/cli-jobs-single-step-scikit-learn-iris-job-docker-context/badge.svg?branch=main)](https://github.com/Azure/azureml-examples/actions/workflows/cli-jobs-single-step-scikit-learn-iris-job-docker-context.yml)|Train a scikit-learn SVM on the Iris dataset using a custom Docker container build.
 [jobs/single-step/scikit-learn/iris/job-sweep.yml](jobs/single-step/scikit-learn/iris/job-sweep.yml)|[![jobs/single-step/scikit-learn/iris/job-sweep](https://github.com/Azure/azureml-examples/workflows/cli-jobs-single-step-scikit-learn-iris-job-sweep/badge.svg?branch=main)](https://github.com/Azure/azureml-examples/actions/workflows/cli-jobs-single-step-scikit-learn-iris-job-sweep.yml)|Sweep hyperparemeters for training a scikit-learn SVM on the Iris dataset.
 [jobs/single-step/scikit-learn/iris/job.yml](jobs/single-step/scikit-learn/iris/job.yml)|[![jobs/single-step/scikit-learn/iris/job](https://github.com/Azure/azureml-examples/workflows/cli-jobs-single-step-scikit-learn-iris-job/badge.svg?branch=main)](https://github.com/Azure/azureml-examples/actions/workflows/cli-jobs-single-step-scikit-learn-iris-job.yml)|Train a scikit-learn SVM on the Iris dataset.
-[jobs/single-step/tensorflow/mnist-distributed-horovod/job.yml](jobs/single-step/tensorflow/mnist-distributed-horovod/job.yml)|[![jobs/single-step/tensorflow/mnist-distributed-horovod/job](https://github.com/Azure/azureml-examples/workflows/cli-jobs-single-step-tensorflow-mnist-distributed-horovod-job/badge.svg?branch=main)](https://github.com/Azure/azureml-examples/actions/workflows/cli-jobs-single-step-tensorflow-mnist-distributed-horovod-job.yml)|Train a basic neural network with TensorFlow on the MNIST dataset, distributed via Horovod.
 [jobs/single-step/tensorflow/mnist-distributed/job.yml](jobs/single-step/tensorflow/mnist-distributed/job.yml)|[![jobs/single-step/tensorflow/mnist-distributed/job](https://github.com/Azure/azureml-examples/workflows/cli-jobs-single-step-tensorflow-mnist-distributed-job/badge.svg?branch=main)](https://github.com/Azure/azureml-examples/actions/workflows/cli-jobs-single-step-tensorflow-mnist-distributed-job.yml)|Train a basic neural network with TensorFlow on the MNIST dataset, distributed via TensorFlow.
 [jobs/single-step/tensorflow/mnist/job.yml](jobs/single-step/tensorflow/mnist/job.yml)|[![jobs/single-step/tensorflow/mnist/job](https://github.com/Azure/azureml-examples/workflows/cli-jobs-single-step-tensorflow-mnist-job/badge.svg?branch=main)](https://github.com/Azure/azureml-examples/actions/workflows/cli-jobs-single-step-tensorflow-mnist-job.yml)|Train a basic neural network with TensorFlow on the MNIST dataset.
 [jobs/basics/hello-code.yml](jobs/basics/hello-code.yml)|[![jobs/basics/hello-code](https://github.com/Azure/azureml-examples/workflows/cli-jobs-basics-hello-code/badge.svg?branch=main)](https://github.com/Azure/azureml-examples/actions/workflows/cli-jobs-basics-hello-code.yml)|*no description*

sdk/python/README.md

@@ -278,7 +278,6 @@ Test Status is for branch - **_main_**
 |jobs|single-step|[iris-scikit-learn](jobs/single-step/scikit-learn/iris/iris-scikit-learn.ipynb)|Run Command to train a scikit-learn SVM on the Iris dataset|[![iris-scikit-learn](https://github.com/Azure/azureml-examples/actions/workflows/sdk-jobs-single-step-scikit-learn-iris-iris-scikit-learn.yml/badge.svg?branch=main)](https://github.com/Azure/azureml-examples/actions/workflows/sdk-jobs-single-step-scikit-learn-iris-iris-scikit-learn.yml)|
 |jobs|single-step|[sklearn-mnist](jobs/single-step/scikit-learn/mnist/sklearn-mnist.ipynb)|Run a Command to train a scikit-learn SVM on the mnist dataset.|[![sklearn-mnist](https://github.com/Azure/azureml-examples/actions/workflows/sdk-jobs-single-step-scikit-learn-mnist-sklearn-mnist.yml/badge.svg?branch=main)](https://github.com/Azure/azureml-examples/actions/workflows/sdk-jobs-single-step-scikit-learn-mnist-sklearn-mnist.yml)|
 |jobs|single-step|[train-hyperparameter-tune-with-sklearn](jobs/single-step/scikit-learn/train-hyperparameter-tune-deploy-with-sklearn/train-hyperparameter-tune-with-sklearn.ipynb)|Train and tune a machine learning model using scikit-learn training scripts to build a to classify iris flower images. - _This sample is excluded from automated tests_|[![train-hyperparameter-tune-with-sklearn](https://github.com/Azure/azureml-examples/actions/workflows/sdk-jobs-single-step-scikit-learn-train-hyperparameter-tune-deploy-with-sklearn-train-hyperparameter-tune-with-sklearn.yml/badge.svg?branch=main)](https://github.com/Azure/azureml-examples/actions/workflows/sdk-jobs-single-step-scikit-learn-train-hyperparameter-tune-deploy-with-sklearn-train-hyperparameter-tune-with-sklearn.yml)|
-|jobs|single-step|[tensorflow-mnist-distributed-horovod](jobs/single-step/tensorflow/mnist-distributed-horovod/tensorflow-mnist-distributed-horovod.ipynb)|Run a **Distributed Command** to train a basic neural network with distributed MPI on the MNIST dataset using Horovod|[![tensorflow-mnist-distributed-horovod](https://github.com/Azure/azureml-examples/actions/workflows/sdk-jobs-single-step-tensorflow-mnist-distributed-horovod-tensorflow-mnist-distributed-horovod.yml/badge.svg?branch=main)](https://github.com/Azure/azureml-examples/actions/workflows/sdk-jobs-single-step-tensorflow-mnist-distributed-horovod-tensorflow-mnist-distributed-horovod.yml)|
 |jobs|single-step|[tensorflow-mnist-distributed](jobs/single-step/tensorflow/mnist-distributed/tensorflow-mnist-distributed.ipynb)|Run a **Distributed Command** to train a basic neural network with TensorFlow on the MNIST dataset|[![tensorflow-mnist-distributed](https://github.com/Azure/azureml-examples/actions/workflows/sdk-jobs-single-step-tensorflow-mnist-distributed-tensorflow-mnist-distributed.yml/badge.svg?branch=main)](https://github.com/Azure/azureml-examples/actions/workflows/sdk-jobs-single-step-tensorflow-mnist-distributed-tensorflow-mnist-distributed.yml)|
 |jobs|single-step|[tensorflow-mnist](jobs/single-step/tensorflow/mnist/tensorflow-mnist.ipynb)|Run a Command to train a basic neural network with TensorFlow on the MNIST dataset|[![tensorflow-mnist](https://github.com/Azure/azureml-examples/actions/workflows/sdk-jobs-single-step-tensorflow-mnist-tensorflow-mnist.yml/badge.svg?branch=main)](https://github.com/Azure/azureml-examples/actions/workflows/sdk-jobs-single-step-tensorflow-mnist-tensorflow-mnist.yml)|
 |jobs|single-step|[train-hyperparameter-tune-deploy-with-keras](jobs/single-step/tensorflow/train-hyperparameter-tune-deploy-with-keras/train-hyperparameter-tune-deploy-with-keras.ipynb)|Train, hyperparameter tune, and deploy a Keras model to classify handwritten digits using a deep neural network (DNN). - _This sample is excluded from automated tests_|[![train-hyperparameter-tune-deploy-with-keras](https://github.com/Azure/azureml-examples/actions/workflows/sdk-jobs-single-step-tensorflow-train-hyperparameter-tune-deploy-with-keras-train-hyperparameter-tune-deploy-with-keras.yml/badge.svg?branch=main)](https://github.com/Azure/azureml-examples/actions/workflows/sdk-jobs-single-step-tensorflow-train-hyperparameter-tune-deploy-with-keras-train-hyperparameter-tune-deploy-with-keras.yml)|