Bump squizlabs/php_codesniffer from 3.11.2 to 3.13.6

Bumps [squizlabs/php_codesniffer](https://github.com/PHPCSStandards/PHP_CodeSniffer) from 3.11.2 to 3.13.6.
- [Release notes](https://github.com/PHPCSStandards/PHP_CodeSniffer/releases)
- [Changelog](https://github.com/PHPCSStandards/PHP_CodeSniffer/blob/4.x/CHANGELOG-3.x.md)
- [Commits](PHPCSStandards/PHP_CodeSniffer@3.11.2...3.13.6)

---
updated-dependencies:
- dependency-name: squizlabs/php_codesniffer
  dependency-version: 3.13.6
  dependency-type: direct:development
...

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Author: dependabot[bot]