Updated Keras and TensorFlow Task Runner and related workspaces.

[tanwarsh]

Related issue #973.

Changes in this PR:

1. Updated Tensorflow and Keras to Tensorflow v2.18.0 and Keras 3
2. Updated openfl/federated/task/runner_kr.py
3. Standardizing the workspace.
4. Removed workspaces.
5. Updated workspaces.
   1. keras_cnn_mnist
   2. keras_nlp
   3. keras_2dunet

[tanwarsh]

I will add code changes for the remaining Keras workspace - Keras_cnn_with_compression and keras_nlp.

@teoparvanov @kta-intel @psfoley, I was facing an issue with optimizer weights due to resetting the weights before saving them to the tensor database and using them to rebuild the model, which resulted in no improvement in accuracy. I have skipped the rebuild (and hence resetting the model optimizer weights) for the first round. This can be further discussed, and we can proceed with these changes once all the pipelines are working and the workspace changes are also completed.

requested changes are done.

[theakshaypant]

Is openfl setup not affected by these changes?

[MasterSkepticista]

A reader cannot tell what this example is about (model/use case). Suggest adding a header (also making the license header consistent with other files) that tells what architecture, and what use case this example is for.

[MasterSkepticista]

I think this is a good place to refactor the directory structure:

openfl-workspace (in future, "examples")
 |_ keras
 |  |_ mnist
 |  |_ lstm
 |_ (other backends in future PRs)

Thoughts?

[teoparvanov]

I think this is a good place to refactor the directory structure:

openfl-workspace (in future, "examples")
 |_ keras
 |  |_ mnist
 |  |_ lstm
 |_ (other backends in future PRs)

Thoughts?

@MasterSkepticista , would it be acceptable to do this in a follow-up PR?

[teoparvanov]

Great work, thanks @tanwarsh ! This PR brings OpenFL back into the TensorFlow game 😉

[tanwarsh]

Is openfl setup not affected by these changes?

No this will not affect openfl setup.

[tanwarsh]

@teoparvanov @MasterSkepticista @kta-intel

As discussed I have migrated workspaces mentioned below to latest tensorflow and keras 3 versions and rest of the workspaces are removed.

1. keras_cnn_mnist
2. keras_nlp
3. keras_2dunet (renamed from tf_2dunet)

[teoparvanov]

LGTM!