[JIRA] (OVIRT-1732) Make 'poll-upstream-chages' job abandon old changes it made

Make 'poll-upstream-chages' job abandon old changes it made ----------------------------------------------------------- Key: OVIRT-1732 URL: https://ovirt-jira.atlassian.net/browse/OVIRT-1732 Project: oVirt - virtualization made easy Issue Type: Bug Components: oVirt CI Reporter: Barak Korren Assignee: infra Labels: poll-upstream-sources, standard-ci The poll-upstream-changes job creates patches when it runs. Not all these patches need or should be merged. When maintainers get around to looking at them, they typically can just merge the latest patch and throw away the rest. The issue is that over time, the patches created by the job can accumulate, and it can be cumbersome for maintainers to remove un-needed ones manually. We should make the poll job remove un-needed patches it made. It needs to look at the last SHA in the upstream-sources.yaml file, and remove all that patches that include an older SHA automatically.