Update dependency irregular-plurals to v4

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
irregular-plurals	^3.2.0 -> ^4.0.0

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Release Notes

sindresorhus/irregular-plurals (irregular-plurals)

### [`v4.0.0`](https://togithub.com/sindresorhus/irregular-plurals/releases/tag/v4.0.0) [Compare Source](https://togithub.com/sindresorhus/irregular-plurals/compare/v3.5.0...v4.0.0) ##### Breaking - Require Node.js 18 [`db10c17`](https://togithub.com/sindresorhus/irregular-plurals/commit/db10c17) - This package is now pure ESM. **Please [read this](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c).**

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