[ENH] Add type hints to get_unchanged_and_required_params_as_str

[nimra06]

Reference Issues/PRs

No existing issue - improving type hints coverage.

What does this implement/fix?

Adds type hints to get_unchanged_and_required_params_as_str() function:

• obj: Any for the parameter
• -> str for the return type

Improves IDE support and enables static type checking.

Does your contribution introduce a new dependency?

No.

Any other comments?

Part of adding type hints throughout the codebase for better tooling support.

[aeon-actions-bot]

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I have added the following labels to this PR based on the title: [ enhancement ].

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