Bump friendsofphp/php-cs-fixer from 3.75.0 to 3.84.0 in /tools (#760)

---
updated-dependencies:
- dependency-name: friendsofphp/php-cs-fixer
  dependency-version: 3.84.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]