build(deps): bump org.pf4j:pf4j in /serverpackcreator-plugin-example

Bumps [org.pf4j:pf4j](https://github.com/pf4j/pf4j) from 3.12.0 to 3.12.1.
- [Release notes](https://github.com/pf4j/pf4j/releases)
- [Changelog](https://github.com/pf4j/pf4j/blob/master/CHANGELOG.md)
- [Commits](https://github.com/pf4j/pf4j/compare/release-3.12.0...release-3.12.1

)

---
updated-dependencies:
- dependency-name: org.pf4j:pf4j
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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