Bump ant from 1.11 to 1.12

Bumps [ant](https://github.com/jenkinsci/ant-plugin) from 1.11 to 1.12.
- [Release notes](https://github.com/jenkinsci/ant-plugin/releases)
- [Changelog](https://github.com/jenkinsci/ant-plugin/blob/master/docs/old-changelog.md)
- [Commits](https://github.com/jenkinsci/ant-plugin/compare/ant-1.11...ant-1.12

)

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

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