Update conditional_step to use convert_xml()
Update conditional_step to use convert_xml()

Change-Id: I7bffb68da221e7ea49db84d0017bf9fa743df93a
Signed-off-by: Thanh Ha <09ea4d3a79c8bee41a16519f6a431f6bc0fd8d6f@linuxfoundation.org>

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