fix: remove deprecated test functions

[mike-r-harris]

Resolves #NUMBER

Description:
Upgraded Commander from v5 to v7
Updated deprecated test functions

Type of change:

• 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)

Why is this change required?:
Keeping changes up to date with latest testing lib versions

Code changes:

• Updated args.js to ensure Commander returns the correct config
• Replaced .equal( with .strictEqual(
• Replaced .notEqual( with .notStrictEqual(
• Replaced .deepEqual( with .deepStrictEqual(

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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 have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.