Update dependency phpunit/phpunit to v9.6.13

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
phpunit/phpunit (source)	9.6.6 -> 9.6.13

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Release Notes

sebastianbergmann/phpunit (phpunit/phpunit)

### [`v9.6.13`](https://togithub.com/sebastianbergmann/phpunit/compare/9.6.12...9.6.13) [Compare Source](https://togithub.com/sebastianbergmann/phpunit/compare/9.6.12...9.6.13) ### [`v9.6.12`](https://togithub.com/sebastianbergmann/phpunit/compare/9.6.11...9.6.12) [Compare Source](https://togithub.com/sebastianbergmann/phpunit/compare/9.6.11...9.6.12) ### [`v9.6.11`](https://togithub.com/sebastianbergmann/phpunit/compare/9.6.10...9.6.11) [Compare Source](https://togithub.com/sebastianbergmann/phpunit/compare/9.6.10...9.6.11) ### [`v9.6.10`](https://togithub.com/sebastianbergmann/phpunit/compare/9.6.9...9.6.10) [Compare Source](https://togithub.com/sebastianbergmann/phpunit/compare/9.6.9...9.6.10) ### [`v9.6.9`](https://togithub.com/sebastianbergmann/phpunit/compare/9.6.8...9.6.9) [Compare Source](https://togithub.com/sebastianbergmann/phpunit/compare/9.6.8...9.6.9) ### [`v9.6.8`](https://togithub.com/sebastianbergmann/phpunit/compare/9.6.7...9.6.8) [Compare Source](https://togithub.com/sebastianbergmann/phpunit/compare/9.6.7...9.6.8) ### [`v9.6.7`](https://togithub.com/sebastianbergmann/phpunit/compare/9.6.6...9.6.7) [Compare Source](https://togithub.com/sebastianbergmann/phpunit/compare/9.6.6...9.6.7)

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