[jnigen] Bump actions/setup-java from 3.11.0 to 3.12.0 (https://github.com/dart-lang/jnigen/issues/338)

Bumps [actions/setup-java](https://github.com/actions/setup-java) from 3.11.0 to 3.12.0.
- [Release notes](https://github.com/actions/setup-java/releases)
- [Commits](https://github.com/actions/setup-java/compare/5ffc13f4174014e2d4d4572b3d74c3fa61aeb2c2...cd89f46ac9d01407894225f350157564c9c7cee2)

---
updated-dependencies:
- dependency-name: actions/setup-java
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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