$ git clone -n https://src.fedoraproject.org/rpms/python-jenkins-job-builder.git /var/lib/mock/f39-build-1606912-38625/root/chroot_tmpdir/scmroot/python-jenkins-job-builder
Cloning into '/var/lib/mock/f39-build-1606912-38625/root/chroot_tmpdir/scmroot/python-jenkins-job-builder'...
$ git fetch origin 97f3bb3900df15e790b2ff1840bb36e921bec2d8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-jenkins-job-builder
 * [new ref]         97f3bb3900df15e790b2ff1840bb36e921bec2d8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 97f3bb3 Fix explicit `Requires:` line