koji_hub: kojira: enable src repo for eln-build also.
    
    See https://pagure.io/releng/issue/9746
    It's desired to have a src repo for eln-build so queries can be done
    against it. This enables this for eln-build. If it turns out to cause
    too many problems we can disable it again.
    
    Signed-off-by: Kevin Fenzi <kevin@scrye.com>