Bump slevomat/coding-standard from 8.11.0 to 8.11.1 in /tools/phpcs

Bumps [slevomat/coding-standard](https://github.com/slevomat/coding-standard) from 8.11.0 to 8.11.1.
- [Release notes](https://github.com/slevomat/coding-standard/releases)
- [Commits](slevomat/coding-standard@8.11.0...8.11.1)

---
updated-dependencies:
- dependency-name: slevomat/coding-standard
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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