[jszip] add string output type

[ffflorian]

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• Test the change in your own code. (Compile and run.)
• Add or edit tests to reflect the change. (Run with npm test.)
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If changing an existing definition:

• Provide a URL to documentation or source code which provides context for the suggested changes: https://stuk.github.io/jszip/documentation/api_zipobject/async.html
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[typescript-bot]

@ffflorian Thank you for submitting this PR!

🔔 @mzeiher @forabi - 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]

👋 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	#41183	diff
Batch compilation
Memory usage (MiB)	100.8	102.8	+2.0%
Type count	17865	17865	0%
Assignability cache size	37564	37566	0%
Language service
Samples taken	316	316	0%
Identifiers in tests	316	316	0%
getCompletionsAtPosition
Mean duration (ms)	577.7	575.7	-0.3%
Mean CV	8.7%	9.1%
Worst duration (ms)	687.5	725.8	+5.6%
Worst identifier	Array	folders
getQuickInfoAtPosition
Mean duration (ms)	574.2	574.6	+0.1%
Mean CV	9.4%	10.0%	+6.4%
Worst duration (ms)	685.7	728.3	+6.2%
Worst identifier	catch	async

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

[typescript-bot]

@ffflorian One or more reviewers has requested changes. Please address their comments. I'll be back once they sign off or you've pushed new commits or comments. Thank you!

[typescript-bot]

🔔 @peterblazejewicz - Thanks for your review of this PR! Can you please look at the new code and update your review status if appropriate?

[peterblazejewicz]

[typescript-bot]

We've gotten sign-off from a reviewer 👏. A maintainer will soon review this PR and merge it if there are no issues. If it shouldn't be merged yet, please leave a comment saying so and we'll wait. Thank you for contributing to DefinitelyTyped!

[ffflorian]

@alloy any chance to get this merged soon? :)

[alloy]

None of the reviewers are current maintainers of these typings, but the change seems innocuous enough and it has been a while already so I think these reviews suffice 👍

[ffflorian]

Thank you :)

[typescript-bot]

I just published @types/jszip@3.1.7 to npm.