Update description_setter to make use of convert_mapping_to_xml()
Update description_setter to make use of convert_mapping_to_xml()

Change-Id: I867dc32453d0f57fd1bc86ccee376a6eaa297615

wikimedia/integration-jenkins-job-builder,OSSystems/jenkins-job-builder,gforcada/jenkins-job-builder,puppetlabs/jenkins-job-builder,dataxu/jenkins-job-builder,phinexus/jenkins-job-builder,puppetlabs/jenkins-job-builder,phinexus/jenkins-job-builder,gforcada/jenkins-job-builder,gforcada/jenkins-job-builder,dataxu/jenkins-job-builder,puppetlabs/jenkins-job-builder,dataxu/jenkins-job-builder,rsig/jenkins-job-builder,dataxu/jenkins-job-builder,wikimedia/integration-jenkins-job-builder,wsoula/jenkins-job-builder,gforcada/jenkins-job-builder,phinexus/jenkins-job-builder,OSSystems/jenkins-job-builder,rsig/jenkins-job-builder,rsig/jenkins-job-builder,rsig/jenkins-job-builder,wikimedia/integration-jenkins-job-builder,wsoula/jenkins-job-builder,wsoula/jenkins-job-builder,gforcada/jenkins-job-builder,wikimedia/integration-jenkins-job-builder,puppetlabs/jenkins-job-builder,phinexus/jenkins-job-builder,phinexus/jenkins-job-builder,OSSystems/jenkins-job-builder,OSSystems/jenkins-job-builder,wikimedia/integration-jenkins-job-builder,wsoula/jenkins-job-builder