Adding Example Annotation with Showcase Notebook

[eshwarprasadS]

Addresses #527

This PR adds an example notebook showing how to leverage SDG to enable annotation use cases.

The PR adds an example notebook showcasing an end-to-end custom use case of annotating (labeling) a classification dataset using the composable components available SDG library, name the Pipeline

[bbrowning]

This looks like a useful example to have in the repository. I rarely use Jupyter notebooks and am not really setup with a way to validate or run this to ensure it works as expected, but perhaps that's something @aakankshaduggal or @khaledsulayman can help with to give this an approval?

Also, we should think of how we keep this updated to ensure it doesn't get stale. The other examples all run as part of our unit test suite in test_examples.py. That may not be possible with a notebook in the same way, but something to think about so we know how we'll keep it working and up-to-date if we can't automatically test it.