$ git clone -n https://src.fedoraproject.org/rpms/rust-gag.git /var/lib/mock/f41-build-side-1-3124893-39482/root/chroot_tmpdir/scmroot/rust-gag
Cloning into '/var/lib/mock/f41-build-side-1-3124893-39482/root/chroot_tmpdir/scmroot/rust-gag'...
$ git fetch origin 7cef70ba445f90013126644bdcb3e9ade8f2f10f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-gag
 * [new ref]         7cef70ba445f90013126644bdcb3e9ade8f2f10f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7cef70b unused leaf package for more than two release cycles