Whatever we create in runroot tasks is owned by root. We change it to be readable by everyone, but that still means it can be hard to delete the composes.

We should run chown at the end of the task as well as the existing chmod.

Whatever user Pungi is running as may not exist in the task environment, so UID should be used. For example Bodhi runs Pungi as apache user, and that is sure not to exist in runroot.