$ git clone -n https://src.fedoraproject.org/rpms/kf6-prison.git /var/lib/mock/f40-build-754759-117976/root/chroot_tmpdir/scmroot/kf6-prison
Cloning into '/var/lib/mock/f40-build-754759-117976/root/chroot_tmpdir/scmroot/kf6-prison'...
$ git fetch origin e7637b6f1f73542eeee39dcac7292f6791568dbb:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kf6-prison
 * [new ref]         e7637b6f1f73542eeee39dcac7292f6791568dbb -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e7637b6 fix: add missing sources