Bump junit from 1.55 to 1.56

Bumps [junit](https://github.com/jenkinsci/junit-plugin) from 1.55 to 1.56.
- [Release notes](https://github.com/jenkinsci/junit-plugin/releases)
- [Commits](https://github.com/jenkinsci/junit-plugin/compare/junit-1.55...junit-1.56

)

---
updated-dependencies:
- dependency-name: org.jenkins-ci.plugins:junit
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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