[BE] - Deprecate colabs

[aclegg3]

Motivation and Context

Colab is a shifting foundtation for hosting tutorials. Back-end changes require updates to installers and scripts resulting in tutorial downtime and extra developer bandwidth load. Instead, we opt to deprecate Colab support and convert existing tutorials to locally-executable Jupyter notebooks.

examples/tutorials/colabs/ directory renamed to examples/tutorials/notebooks/

TODO: we should add a quick resource page telling users how to install and run Jupyter notebooks.

How Has This Been Tested

Tested all refactored .ipynb tutorials on local Jupyter notebook server.

Types of changes

• [x] Docs change / refactoring / dependency upgrade
• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• [x] My code follows the code style of this project.
• [x] My change requires a change to the documentation.
• [x] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [x] I have completed my CLA (see CONTRIBUTING)
• [ ] I have added tests to cover my changes.
• [x] All new and existing tests passed.