Bump phpbench/phpbench from 1.5.1 to 1.6.1

Bumps [phpbench/phpbench](https://github.com/phpbench/phpbench) from 1.5.1 to 1.6.1.
- [Release notes](https://github.com/phpbench/phpbench/releases)
- [Changelog](https://github.com/phpbench/phpbench/blob/master/CHANGELOG.md)
- [Commits](phpbench/phpbench@1.5.1...1.6.1)

---
updated-dependencies:
- dependency-name: phpbench/phpbench
  dependency-version: 1.6.1
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]