Demonstrate script testing/debugging in the script mode walkthroughs

[athewsey]

Feature request

We already provide example shell commands to invoke and test training scripts for all variants of the migration challenge. For example from SKLearn:

!python3 src/main.py \
    --train ./data/train \
    --test ./data/test \
    --model_dir ./data/model \
    --class_names {class_names_str} \
    --n_estimators=100 \
    --min_samples_leaf=3

Since this is the recommended debugging workflow, we should also demonstrate it in the script mode walkthroughs by adding equivalent commands in the 'SageMaker' variants of these notebooks - before the Estimator gets created.

This will help these notebooks illustrate the process/workflow of translating from in-notebook to notebook+job, better than just showing the final result.

Background

Today, we use in-notebook shell commands as the recommended script debugging workflow for the migration challenge - because our options are somewhat constrained for a workshop:

• SageMaker Warm Pools requires a quota increase to enable
• SageMaker Local Mode isn't natively supported in Studio at this time
• SageMaker SSH Helper has a bit of a learning curve for any data scientists not already familiar with online SSH-based debugging (and some setup required - although we could probably automate that).

We talk about these other options in the post-challenge wrap-up, but don't want to confuse the issue by introducing them up-front in the code.