Change notebook parameters to snake case

Sets all parameters in the first cell of the notebooks to use snake case. This caused issues with parity tests between the old and new CLI.

Description

Instead of changing all variable names throughout the notebook this renames the variable in the first cell and adds a second cell to continue using the previous variable name.

Done to minimise the changes made and as the non-snake-case variables do make sense in some cases (e.g. variable name matching a key name).

How Has This Been Tested?

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Relevant Documents (optional)

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• Chore (non-code changes, e.g. comments, readme, grammar, etc...)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I added tests where appropriate.

Reviewers

@schmidtp @ahmedk @kluyvert