[fuzzyset] - Make sure optional params remain optional

[narainsagar]

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[narainsagar]

Hi @lgrignon Can you please review this change? Thanks!

[lgrignon]

+1

[typescript-bot]

@narainsagar Thank you for submitting this PR!

🔔 @lgrignon - please review this PR in the next few days. Be sure to explicitly select Approve or Request Changes in the GitHub UI so I know what's going on.

If no reviewer appears after a week, a DefinitelyTyped maintainer will review the PR instead.

[typescript-bot]

A definition author has approved this PR ⭐️. A maintainer will merge this PR shortly. If it shouldn't be merged yet, please leave a comment saying so and we'll wait. Thank you for your contribution to DefinitelyTyped!