$ git clone -n https://src.fedoraproject.org/rpms/rust-skeptic.git /var/lib/mock/f42-build-side-1-3583165-46888/root/chroot_tmpdir/scmroot/rust-skeptic
Cloning into '/var/lib/mock/f42-build-side-1-3583165-46888/root/chroot_tmpdir/scmroot/rust-skeptic'...
$ git fetch origin c8a90cd97ec74ca8232bb6a327c42aac167ad848:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-skeptic
 * [new ref]         c8a90cd97ec74ca8232bb6a327c42aac167ad848 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c8a90cd no longer needed