Bump redhat-plumbers-in-action/differential-shellcheck from 4 to 5

Bumps [redhat-plumbers-in-action/differential-shellcheck](https://github.com/redhat-plumbers-in-action/differential-shellcheck) from 4 to 5.
- [Release notes](https://github.com/redhat-plumbers-in-action/differential-shellcheck/releases)
- [Changelog](https://github.com/redhat-plumbers-in-action/differential-shellcheck/blob/main/docs/CHANGELOG.md)
- [Commits](https://github.com/redhat-plumbers-in-action/differential-shellcheck/compare/v4...v5

)

---
updated-dependencies:
- dependency-name: redhat-plumbers-in-action/differential-shellcheck
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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