$ git clone -n https://src.fedoraproject.org/rpms/rust-ct-logs.git /var/lib/mock/f41-build-side-1-2928763-35102/root/chroot_tmpdir/scmroot/rust-ct-logs
Cloning into '/var/lib/mock/f41-build-side-1-2928763-35102/root/chroot_tmpdir/scmroot/rust-ct-logs'...
$ git fetch origin 8291aa5f27f77c8c5b02cbe81c28dff4d1d18864:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-ct-logs
 * [new ref]         8291aa5f27f77c8c5b02cbe81c28dff4d1d18864 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8291aa5 unused leaf package for more than two release cycles