Fix release jobs losing their parameters on Jenkins restart

After a Jenkins master restart, the Nuxeo release jobs (see the release-* jobs) don't offer the "Build with Parameters" action, but only "Build Now", as if the jobs didn't detect the parameters defined inside the Jenkinsfile, such as:

  parameters {
    string(name: 'BUILD_VERSION', defaultValue: '', description: 'Version of the Nuxeo Server build to promote')
  }

in the Nuxeo release pipeline.

This is a known Jenkins issue.