Bump docker-fixtures from 1.11 to 1.12 (#480)
Bump docker-fixtures from 1.11 to 1.12 (#480)

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

---
updated-dependencies:
- dependency-name: org.jenkins-ci.test:docker-fixtures
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>

Co-authored-by: dependabot[bot] <1c358da00a777d4e9898c1280ab801e2df165188@users.noreply.github.com>
jenkinsci/pipeline-maven-plugin,jenkinsci/pipeline-maven-plugin