slick-carousel: Provide typing for the focusOnChange property.

[altearius]

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[typescript-bot]

👋 Hi there! I’ve run some quick measurements against master and your PR. These metrics should help the humans reviewing this PR gauge whether it might negatively affect compile times or editor responsiveness for users who install these typings.

Let’s review the numbers, shall we?

Comparison details 📊

	master	#41148	diff
Batch compilation
Memory usage (MiB)	93.3	92.6	-0.8%
Type count	16089	16089	0%
Assignability cache size	33376	33376	0%
Language service
Samples taken	235	236	0%
Identifiers in tests	235	236	0%
getCompletionsAtPosition
Mean duration (ms)	415.9	419.7	+0.9%
Mean CV	9.3%	9.3%
Worst duration (ms)	520.7	506.3	-2.8%
Worst identifier	on	slick
getQuickInfoAtPosition
Mean duration (ms)	414.5	419.3	+1.2%
Mean CV	9.7%	9.4%	-3.1%
Worst duration (ms)	506.5	511.2	+0.9%
Worst identifier	on	slidesToShow

It looks like nothing changed too much. I won’t post performance data again unless it gets worse.

[typescript-bot]

@altearius Thank you for submitting this PR!

🔔 @Kocal - 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 owner 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!