[@types/istanbul-lib-coverage] Update typings

[lorenzorapetti]

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• Provide a URL to documentation or source code which provides context for the suggested changes: Migrate @jest/reporters to TypeScript jestjs/jest#7994
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[typescript-bot]

@loryman Thank you for submitting this PR!

🔔 @jason0x43 - 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]

After 5 days, no one has reviewed the PR 😞. A maintainer will be reviewing the PR in the next few days and will either merge it or request revisions. Thank you for your patience!

[typescript-bot]

I just published @types/istanbul-lib-coverage@2.0.0 to npm.