Add new Vision Transformer tutorial using experimental workflow interface

[kta-intel]

This tutorials demonstrates how to set up a basic OpenFL workload using the experimental workflow interface to fine-tune a vision transformer model on the medmnist dataset.

This notebook makes use of standard pytorch practices and leverages HuggingFace's transformer library to build a vision transformer with a pretrained backbone and custom classification head for an image classification workload using medmnist.

It is heavily modeled after the 101_MNIST workflow tutorial

[psfoley]

Could you renumber this example to something like Workflow_Interface_102_Vision_Transformer.ipynb?

[kta-intel]

sure, all set!

[psfoley]

Hi @kta-intel! This PR looks good. Once the number of the example is changed I think this is ready to merge.

[manuelhsantana]

When I install !pip install -r requirements_vision_transformer.txt in a clean environment with only openFL, I got an error with torch version:
ERROR: Could not find a version that satisfies the requirement torch==2.0.1+cpu (from versions: 1.4.0, 1.5.0, 1.5.1, 1.6.0, 1.7.0, 1.7.1, 1.8.0, 1.8.1, 1.9.0, 1.9.1, 1.10.0, 1.10.1, 1.10.2, 1.11.0, 1.12.0, 1.12.1, 1.13.0, 1.13.1, 2.0.0, 2.0.1, 2.1.0, 2.1.1, 2.1.2)
ERROR: No matching distribution found for torch==2.0.1+cpu

[manuelhsantana]

LGTM!
I ran the workflow from the beginning to the end and it ran without any problems!
Great Work Kevin!