[JIRA] (OVIRT-1877) Update docs to indicated adding 'jenkins:' prefix to build URLs

Update docs to indicated adding 'jenkins:' prefix to build URLs --------------------------------------------------------------- Key: OVIRT-1877 URL: https://ovirt-jira.atlassian.net/browse/OVIRT-1877 Project: oVirt - virtualization made easy Issue Type: Improvement Components: Documentation Reporter: Barak Korren Assignee: infra Our infra includes multipile places where users can input text that is used as configuration for repoman. Users are typically expected to place URLs of build jobs there to make repoman acquire built artifacts (For e.g. testing). So far documentation specified that the plain URL to the build job can be used. This turns out to only be true for builds made on jenkins.ovirt.org. For URLs pointing at other jenkins servers, the '{{jenkins:}}' prefix needs to be added. Documentation should be updated to teach users to add the '{{jenkins:}}' prefix.