Update helpers.artifactory
Update helpers.artifactory

- Update helpers.artifactory_optional_props to use convert xml

Change-Id: Ib6ea675121a2cddd8e7df357b9b7855c41758529
Signed-off-by: Kien Ha <3e36ebd6a7c89ee7d9a20a5fbbffc571f107e566@gmail.com>

puppetlabs/jenkins-job-builder,onshape/jenkins-job-builder,onshape/jenkins-job-builder,dataxu/jenkins-job-builder,wikimedia/integration-jenkins-job-builder,puppetlabs/jenkins-job-builder,onshape/jenkins-job-builder,dataxu/jenkins-job-builder,gforcada/jenkins-job-builder,wikimedia/integration-jenkins-job-builder,tamac-io/jenkins-job-builder,OSSystems/jenkins-job-builder,phinexus/jenkins-job-builder,wsoula/jenkins-job-builder,wikimedia/integration-jenkins-job-builder,OSSystems/jenkins-job-builder,wsoula/jenkins-job-builder,phinexus/jenkins-job-builder,OSSystems/jenkins-job-builder,tamac-io/jenkins-job-builder,puppetlabs/jenkins-job-builder,rsig/jenkins-job-builder,dataxu/jenkins-job-builder,puppetlabs/jenkins-job-builder,twc-openstack/jenkins-job-builder,twc-openstack/jenkins-job-builder,twc-openstack/jenkins-job-builder,tamac-io/jenkins-job-builder,tamac-io/jenkins-job-builder,onshape/jenkins-job-builder,phinexus/jenkins-job-builder,phinexus/jenkins-job-builder,dataxu/jenkins-job-builder,gforcada/jenkins-job-builder,gforcada/jenkins-job-builder,wsoula/jenkins-job-builder,gforcada/jenkins-job-builder,rsig/jenkins-job-builder,OSSystems/jenkins-job-builder,phinexus/jenkins-job-builder,rsig/jenkins-job-builder,wsoula/jenkins-job-builder,rsig/jenkins-job-builder,twc-openstack/jenkins-job-builder,wikimedia/integration-jenkins-job-builder,wikimedia/integration-jenkins-job-builder,gforcada/jenkins-job-builder