chore(deps): update dependency cssnano to v5.1.13

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
cssnano	5.1.12 -> 5.1.13

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Release Notes

cssnano/cssnano

### [`v5.1.13`](https://togithub.com/cssnano/cssnano/releases/tag/cssnano%405.1.13) [Compare Source](https://togithub.com/cssnano/cssnano/compare/cssnano@5.1.12...cssnano@5.1.13) #### Bug Fixes - fix TypeScript type of `cssnano()` return value (https://github.com/cssnano/cssnano/commit/b92dbe3ab1db16141dc6296cd350f3fdf5c2defe)

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Configuration

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